Part 1

LITTLE BLUE BOOK NO. 452 Edited by E. Haldeman-Julius

A Dictionary of Scientific Terms

Leo Markun

HALDEMAN-JULIUS PUBLICATIONS GIRARD, KANSAS

Copyright, 1927 Haldeman-Julius Company

PRINTED IN THE UNITED STATES OF AMERICA

A DICTIONARY OF SCIENTIFIC TERMS

PREFACE

Completeness is a virtue which this little Blue Book cannot, in the nature of things, possess. If any reader is disappointed not to find it here, I must respectfully direct his attention to the three ponderous tomes which make up a well-known dictionary of chemistry, to the still larger and more numerous volumes devoted to a dictionary of applied physics, and to other similar works. The sciences are many, and the words which they employ exclusively or in senses peculiar to themselves are exceedingly numerous.

Physics, chemistry, and biology contribute the greatest number of words to the present dictionary. A few terms used in other sciences are included, chiefly to show what I believe the proper scope of a dictionary of scientific terms to be. There is a genuine need for a large dictionary, which ought to be of about the same size as Webster’s Collegiate or the Oxford Concise, and which should deal with the vocabularies of economics, anthropology, sociology, and psychology as well as with those of mechanics, geology, astronomy, and all the older sciences. Such a dictionary should be written by specialists in the various fields of knowledge with the aid of a skilled etymologist, and under the supervision of an editor who is not himself a professional scientist. It would be his special task to see that the definitions are intelligible to non-specialists, and to literate laymen in particular.

Of course no dictionary can take the place of primers of the sciences. There are a number of excellent ones in this series, some of which I referred to in writing this book. It is in many cases impossible to give adequate explanations in a few words. Besides, the scientific writers themselves frequently quarrel about the true meaning of such a word as _ether_ or _instinct_.

I have dealt here with a number of words which are of significance when we try to set the limits of science. _Common sense_, _philosophy_, _theology_, and _superstition_ are examples. The claims of several branches of knowledge to be considered sciences are also taken up.

A DICTIONARY OF SCIENTIFIC TERMS

_Abasia._ The inability to walk, especially when it is caused by mental disorder.

_Abdomen._ The hind part of insects, spiders, etc. The belly, including the nutritive organs.

_Aberrant._ Diverging from normal type.

_Aberration._ The non-convergence of rays of light to a focus. The apparent displacement of the true position of a heavenly body.

_Abiogenesis._ Spontaneous generation.

_Abnormal._ Deviating from type.

_Aborigines._ The inhabitants of a region, or, in some cases, the plants and animals, found by colonists. Literally, those that have been in the land from the beginning of things.

_Abort._ Have premature delivery of a child. Remain undeveloped or sterile, or dwindle away.

_Absolute._ Pure. The absolute, philosophically speaking, is final and total reality.

_Absorption._ Disappearance through incorporation in something else. The solution of a gas in a liquid is called absorption. Rays of light may be absorbed in some mediums.

_Abstract._ Theoretical, aside from particular instances.

_Abulia._ Weakness of will.

_Abyssal._ Relating to the depths of the sea.

_Acaulescent._ Apparently stemless.

_Acceleration._ Rate of increase of velocity per time unit. Rate of change of the velocity of a chemical reaction. The acceleration of a star is the time it gains daily over the sun.

_Accident._ A property which is not essential to our conception of a subject.

_Achene._ A small, dry, indehiscent, one-seeded fruit.

_Achromatic._ Colorless, transmitting light without decomposing it.

_Acid._ A substance that neutralizes and is neutralized by a base, and which contains hydrogen. A compound that produces hydrogen ions when it decomposes in aqueous solution.

_Actinium._ A radioactive substance, believed to be an element.

_Actinozoan._ One of a class of coelenterates including the corals.

_Aculeate._ Having a sting, prickly.

_Acuminate._ Tapering to a point.

_Adiabatic._ Maintaining a constant temperature.

_Adrenalin._ A crystalline substance obtained from suprarenal extract.

_Adsorption._ The condensation of dissolved substances on the surface of a liquid or solid.

_Adventitious._ Not in the usual place, as a root.

_Aerial._ Atmospheric.

_Affect._ Disease, emotional complex.

_Afferent._ Conducting inward.

_Agoraphobia._ The morbid fear of public places.

_Agronomics._ The science of crop production. The scientific management of land.

_Agrostology._ The study of the grasses.

_Air._ The atmosphere, a gaseous substance of which oxygen and nitrogen are the principal constituents.

_Air pump._ A pump for forcing air into, or taking it out of, hollow places.

_Albino._ An animal, especially a human being, characterized by the congenital absence of coloring pigment in the skin, hair, and eyes. The typical albino has very light skin and hair and pink eyes.

_Albumen._ A substance, usually edible, found between the skin embryo of seeds.

_Albumin._ A class of proteids found in blood serum, milk, and muscle.

_Alcohol._ Ethyl alcohol, the substance which causes intoxication, and a whole class of substances which are similar to it. They are hydroxides of organic radicals.

_Alga._ Seaweed. Chiefly used in the plural: algae.

_Alkali._ Caustic hydroxides which form soluble soaps with fatty acids and turn red litmus paper blue.

_Allotropy._ Variation of physical properties without change of substance. Carbon, for example, may exist as lampblack, graphite, or the diamond.

_Alloy._ A mixture (not a compound) of metals.

_Alluvium._ The deposit of earth and other materials by the mechanical action of running water. More familiar is the adjective: alluvial.

_Alpha rays._ Becquerel rays which have less power of penetration than beta rays but greater power of inducing conductivity in gases.

_Alpine._ Relating to a mountain district so high that it has arctic climate.

_Alum._ A double sulphate of aluminium and potassium. Other sulphates of similar crystalline form are also known as alums.

_Aluminium._ A metallic element. The spelling given is the usual one in Great Britain, and it is also the one employed by American chemists. In ordinary use in the United States: aluminum. The symbol: Al.

_Amalgam._ An alloy containing mercury. To amalgamate is to form an amalgam.

_Ammeter._ An instrument for measuring the strength of electric currents in amperes.

_Amorphous._ Uncrystallized.

_Ampere._ Sometimes spelled: ampère. The unit of electric current, the current that one volt can send through one ohm.

_Amphibia._ A division of Vertebrata, intermediate between reptiles and fishes, including the frog. The study of Amphibia is known as amphibiology.

_Amplexicaul._ Encircling or clasping a stem.

_Anabolism._ Constructive metabolism.

_Analogy._ Functional correspondence between parts of different origin and structure.

_Analysis._ Resolution into simple elements, as by chemical processes. In mathematics, algebraic investigation.

_Anandrous._ Without stamens.

_Anaphylaxis._ Excessive susceptibility to an albuminous substance.

_Anatomy._ The science of bodily structure.

_Anemograph._ An instrument for recording the direction and force of wind.

_Aneroid barometer._ A barometer in which there is no liquid, the pressure of the air being measured by its action on the elastic lid of a box in which a partial vacuum has been created.

_Angiosperm._ A plant of a class which has its seeds in a closed ovary.

_Anhydrous._ Without water of crystallization or water in general.

_Animal._ A living being distinguished from plants in that it is capable of voluntary motion and sensation. Some recent investigations appear to lead to the conclusion that other differentia will have to be adopted. The human being, incidentally, is an animal, although popular language sometimes distinguishes man from the animals.

_Animalcule._ A minute animal, usually one which cannot be seen with the naked eye.

_Anion._ A negative ion.

_Annual._ A plant that lives only for a year.

_Annulate_, _annulated_. Ringed.

_Anode._ A positive electrode.

_Antenna._ Feeler, sensory organ found in pairs on heads of insects and crustacea. Irritable processes found in some male flowers. An elevated conductor for receiving or transmitting electric waves. Plural: antennæ.

_Anther._ The part of the stamen which contains the pollen.

_Anthropogeography._ The science which treats of geography as applied to man. That part of anthropology dealing with the effect of the environment on human beings. There are a number of compounds beginning with anthro-. The meaning may often be understood by remembering that the Greek word _anthropos_ means man, not as opposed to woman but as excluding the non-human.

_Anthropology._ The study of man as an animal, with respect to race, distribution, culture, and social organization.

_Anticlinal._ Forming a ridge with strata leaning in opposite directions from an axis. Having an upright spine toward which spines on both sides lean.

_Anticyclone._ An outward and rotary flow of air from an atmospheric area of high pressure.

_Antidote._ A medicine used to counteract a poison or disease.

_Antimony._ An element of metallic appearance. Symbol: Sb.

_Anus._ The posterior opening of the alimentary canal.

_Apetalous._ Without petals.

_Aphasia._ Loss of speech from a brain injury.

_Aphelion._ The point in the orbit of a planet or comet farthest from the sun.

_Apheliotropic._ Turning away from the sun.

_Apogee._ The point in the orbit of a planet or the moon where it is farthest from the earth.

_Aponeurosis._ The flat, dense connective tissue covering and forming the attachments of certain muscles.

_Aquatic._ Growing or living in or near the water.

_Arachnida._ A class of animals including spiders and scorpions.

_Arachnoid._ Covered with long, thin hairs. A serous membrane enveloping the brain and spinal cord.

_Arboreal._ Living in or connected with trees.

_Archeology._ The study of prehistoric antiquity, or sometimes of antiquity which is not prehistoric.

_Archean._ Also: Archaean. Relating to the earliest geological period.

_Arenicolous._ Living in the sand.

_Argon._ A gaseous element found in the atmosphere in small amounts. Symbol: A.

_Arsenic._ A semi-metallic element. Symbol: As.

_Art._ Skill of various sorts. Knowledge from the practical point of view. H. W. Fowler distinguishes it from science: “Science knows, art does; a science is a body of connected facts, an art is a set of directions; the facts of science (errors not being such) are the same for all people, circumstances, and occasions; the directions of art vary with the artist and the task.” According to the Oxford English Dictionary: “The distinction as commonly apprehended is that a science is concerned with theoretic truth, and an art with methods for effecting certain results. Sometimes, however, the term _science_ is extended to denote a department of practical work which depends on the knowledge and conscious application of principles; an art, on the other hand, being understood to require merely knowledge of traditional rules and skill acquired by habit.”

_Articulation._ A joint, as between bones or parts of plants, especially between parts which may separate at any time.

_Ascendant._ Rising toward the zenith.

_Asexual._ Without sex.

_Assay._ A sort of analysis, especially of metals.

_Association._ Mental connection. The word has also three or four meanings in chemistry, which cannot be explained briefly.

_Asteroid._ A minor planet.

_Astronomy._ The science of the heavenly bodies.

_Astrophysics._ The science which deals with the constitution of the heavenly bodies. It is a branch of astronomy.

_Atmosphere._ The gaseous envelope about a heavenly body. Especially the air which surrounds the earth. As a measurement, a pressure of fifteen pounds per square inch.

_Atom._ The smallest particle of an element that enters into combination. According to old definitions, it is indivisible.

_Aurora._ A luminous atmospheric phenomenon. The aurora borealis radiates from the north magnetic pole, the aurora australis from the south magnetic pole of the earth.

_Avogadro’s Hypothesis._ The assumption that equal volumes of gases contain equal numbers of molecules if conditions of temperature and pressure are the same. It appears to be close to the truth.

_Axiom._ A truth which is considered self-evident.

_Bacillus._ One of a sort of rod-shaped bacteria. Loosely, any bacterium. Plural: bacilli. The Oxford English Dictionary distinguishes bacillus from bacterium, “with which it agrees in its rodlike form, and characterized by its larger size and mode of reproduction.”

_Bacterium._ More familiar in plural: bacteria. A group of vegetable microörganisms. Not all cause disease.

_Barbarian._ Of a civilization intermediate between one which is called savage and the most complex forms.

_Barium._ A silver-white element, classed as a metal. Symbol: Ba.

_Barometer._ An instrument used to measure atmospheric pressure, and thus to predict storms or determine altitudes.

_Base._ A substance which can neutralize acids to form a salt. The term includes alkalis. Part of an organ (of a plant or animal) attached to another organ which is more central.

_Batrachia._ An order of amphibians which have no tails in the adult stage.

_Battery._ A system of cells (sometimes used for a single cell) which changes chemical energy into electricity.

_Becquerel rays._ Rays emitted by radium and other substances which are susceptible to deflection by electricity and which electrically charge other bodies.

_Behaviorism._ Watson’s psychological system. Opposed to introspective psychology, and it emphasizes the physiology of human behavior.

_Bessemer steel._ Steel made from cast iron by a process which burns out carbon, sulphur, and phosphorus.

_Beta rays._ Becquerel rays which are apparently identical with cathode rays.

_Bichloride._ A compound in which there are two atoms of chlorine in the molecule.

_Biennial._ A plant that rises one year and flowers, fructifies, and dies the next.

_Binary._ Composed of two elements.

_Biochemistry._ The chemical study of living organisms and their products.

_Biology._ The science of living organisms.

_Biophore._ The indivisible unit of life. The biophore cannot support life if split up.

_Bird._ One of a class of feathered and warm-blooded vertebrate animals.

_Bisexual._ Pertaining to, or containing the organs of, both sexes.

_Bismuth._ A metallic element. Symbol: Bi.

_Boron._ A non-metallic solid element. Symbol: B.

_Botany._ The science of plants.

_Boyle’s Law._ The theory that the pressure exerted by air is directly proportional to its density. This is now believed to be true only approximately.

_Brachycephalic._ Pertaining to skulls of which the breadth is at least four-fifths of the length. Short-headed.

_Brass._ An alloy of copper and zinc.

_British Thermal Unit._ The amount of heat which is capable of raising the temperature of one pound of water by one degree Fahrenheit. The usual abbreviation: B.T.U.

_Bromine._ A liquid element. Symbol: Br.

_Bronze._ An alloy of copper and tin, usually with small amounts of zinc.

_Brownian movement._ A movement of minute drops of oil suspended in stagnant air, apparently due to molecular motion.

_Bunsen burner._ A sort of burner much used by chemists, within which air and fuel gas are mixed.

_Burn._ To oxidize in such a way that heat and light are produced.

_Cadmium._ A metallic element. Symbol: Cd.

_Caesium._ A metallic element. Symbol: Cs. It somewhat resembles potassium.

_Calcium._ A metallic element. Symbol: Ca. Compounds of calcium are common, but the element is not to be found in a pure state.

_Calculus._ Solid concretion in the body. A branch of mathematics, differential and integral calculus, which deals with problems of constant variation or motion, and which has been of great importance in modern science.

_Calorie._ The unit of heat, the amount of heat necessary to raise the temperature of a gram of water one degree Centigrade. This is the small calorie. Confusion sometimes results because the large calorie, which is one thousand times the small one, is called simply the calorie, without any qualification, in discussions about food. It is sometimes known as the great calorie. The small calorie is best called the gram-calorie.

_Calorimeter._ An instrument for measuring quantities (not degrees) of heat.

_Calyx._ The outer case of a bud.

_Cambrian._ Relating to the lowest of the Paleozoic rocks and the earliest part of the Paleozoic period.

_Candlepower._ The unit of illumination, measured by a standard candle. The illumination produced one foot away from a standard candle is the candle foot.

_Capillarity_ or _capillary attraction_. A phenomenon best illustrated in very slender (capillary) tubes, in which the liquid rises, or, if it does not wet the tube, sinks. In the latter case we speak of capillary repulsion.

_Capital._ In economics, wealth employed for the purpose of production.

_Carbolic acid._ Phenol, not a true acid.

_Carbon._ An element which exists in three allotropic forms. Symbol: C. The oxides are important, and there are many organic compounds.

_Carboniferous._ Pertaining to a Paleozoic (geological) period following the Devonian.

_Carburetor_ or _carburettor_. A device which mixes air with petroleum vapor, or one which puts illuminants into water gas.

_Cardio--._ Heart--, in many combinations.

_Carina._ A ridge-shaped structure.

_Carnivora._ The flesh-eating mammals.

_Carpel._ An organ which is part of the pistil.

_Catabolism._ Destructive metabolism.

_Catalysis._ The effect produced by a substance (called the catalyst, the catalytic agent, or the catalyzer) which aids a chemical change in other bodies, undergoing no change of its own.

_Cathode rays._ Rays discharged from the cathode (negative pole) of a vacuum tube. They are considered streams of electrons, which may be projected at a velocity of 100,000 miles per second.

_Caudal._ Relating to the tail.

_Cause._ That which brings about something else (an effect). Professor Adam Leroy Jones says: “It has been objected that we can never observe one thing producing another; that we can at most observe that one thing is followed by another, and perhaps find reason for believing that it will always have such connection; and that to say that A _produces_ B, is to raise a metaphysical question with which science and everyday thinking are not concerned.... Is it sufficient to say that cause means simply invariable connection? No, for the succession of day and night is an invariable succession. The notion of cause implies that the relation of cause and effect not only _is_ invariable, but also that it must _be_ so; that there is an _unconditional_ or necessary connection between the two; that if the first does not happen, the second cannot.... A causal law is a statement, in general terms, of a causal connection.”

_Cell._ A battery unit, a device for changing chemical energy into electricity. The structural unit of which living beings are composed. An enclosed cavity in an organism or a mineral. A covering which protects the eggs or the young of certain animals.

_Celsius._ Centigrade (thermometer).

_Cenogetic._ Pertaining to individual development which does not repeat the development of the group of which the individual is a member.

_Cenozoic._ Relating to the geological age of the mammals. It is still in existence.

_Center of gravity._ The point in a body where its entire weight may be assumed to be concentrated.

_Centigrade._ A thermometer, or the scale on which it is based, with the boiling point of water at 100 and the freezing point at zero, under standard conditions of pressure. Abbreviation: C. Such a scale is far more useful to scientists than that of Fahrenheit.

_Centimeter._ One hundredth of a meter.

_Centrifugal._ Flying or tending to fly away from the center.

_Centripetal._ Tending to move toward the center.

_Centrosome._ A minute body found in the cytoplasm or the nucleus of some (biological) cells.

_Centrum._ The center of an earthquake.

_Cephalic._ Relating to the head.

_Cephalopoda._ The highest class of mollusks.

_Cereal._ A grass which produces edible grain.

_Cerium._ A metallic element. Symbol: Ce.

_Cetacea._ The order of mammals including the whales.

_Chemistry._ The science which deals with the composition of matter and its transformations.

_Chiroptera._ An order containing the bats.

_Chloride._ A chlorine compound.

_Chlorine._ A gaseous element. Symbol: Cl.

_Chlorophyll._ The coloring-matter of green parts of plants.

_Chromatic aberration._ The colored fringe seen at the edges of images formed by a simple lens, because of the difference in wave lengths of the various rays.

_Chromium._ A metallic element. Symbol: Cr.

_Chromo-._ Color-, in many compounds. Also: chroma-, chromato-.

_Chromosome._ One of the small bodies formed out of a protoplasmic substance (chromatin) in the nucleus before a cell divides.

_Civilization._ An advanced stage of culture. Civilization is sometimes contrasted with culture, but the matter is one which cannot be considered here.

_Class._ A group of animals or plants, more comprehensive than an order and less so than a phylum.

_Climate._ The average weather conditions of a particular place or region.

_Cobalt._ A metallic element. Symbol: Co.

_Coccus._ A spherical bacterium. A sort of carpel.

_Coelenterata._ A phylum of invertebrate animals including the corals.

_Cohesion._ Molecular attraction within a body.

_Colloid._ Not crystalloid. A substance which does not form a true solution. Colloidal liquids have very little osmotic pressure.

_Columbium_ or _niobium_. A metallic element. Symbol: Cb.

_Combustion._ Oxidation accompanied by the production of heat and light. Less frequently, the word is used for a combination which is not oxidation or where no heat or light is produced.

_Common sense._ Ordinary and non-scientific thought processes. Scientific thinking is more exact and more fertile.

_Community._ A social group.

_Comparative._ Involving comparison, as between man and the other animals.

_Complex._ In psycho-analysis, a cluster of ideas and mental images joined together by a stressed emotion; especially such a cluster that is thrust out of consciousness (repressed).

_Component of a force._ The effective value of a force in a given direction.

_Compound._ A substance consisting of two or more chemical elements in combination.

_Compound animal, flower, leaf, etc._ An animal, etc., consisting of a combination of organisms or simple parts.

_Conation._ Will, directing power, effort.

_Concave._ Curved like the interior of a circle or sphere.

_Concept_ or _conception_. The idea, notion, or thought held about anything. Conception includes symbol and meaning.

_Condense._ Change from gas to liquid. Concentrate (electricity). Of organic compounds, react in a certain way so as to form new bonds.

_Conduct._ Carry heat or electricity.

_Conductance._ Ability to conduct. The word is used to describe the property of a conductor.

_Conductivity._ Power to conduct (heat or electricity).

_Conductor._ That which readily conducts (heat or electricity).

_Congeal._ Solidify, freeze.

_Connate._ United from the beginning.

_Constant._ A quantity that does not vary, or one that does not change under given conditions.

_Convex._ Curved like the outside of a circle or sphere.