Columbia Encyclopedia

Search results

403 results found

chlamydia

(Encyclopedia)chlamydia kləmĭdˈēə [key], genus of microorganisms that cause a variety of diseases in humans and other animals. Psittacosis, or parrot fever, caused by the species Chlamydia psittaci, is transmi...

fallout

(Encyclopedia)fallout, minute particles of radioactive material produced by nuclear explosions (see atomic bomb; hydrogen bomb; Chernobyl) or by discharge from nuclear-power or atomic installations and scattered th...

iritis

(Encyclopedia)iritis īrīˈtĭs [key], inflammation of the iris, the pigmented portion of the eye surrounding the pupil. The condition is sometimes associated with diabetes, with rheumatic diseases such as rheumat...

inoculation

(Encyclopedia)inoculation, in medicine, introduction of a preparation into the tissues or fluids of the body for the purpose of preventing or curing certain diseases. The preparation is usually a weakened culture o...

Agriculture, United States Department of

(Encyclopedia)Agriculture, United States Department of, federal executive department established in 1862, whose head was made a cabinet member in 1889. The department administers federal programs related to food pr...

biometrics, in biology

(Encyclopedia)biometrics, also known as biostatistics or biometry, in biology, the development and application of statistical and mathematical methods to the analysis of data resulting from biological observations ...

tetracycline

(Encyclopedia)tetracycline tĕˌtrəsīˈklēn [key], any of a group of antibiotics produced by bacteria of the genus Streptomyces. Effective against a wide range of Gram positive and Gram negative bacteria, tetrac...

barley

(Encyclopedia)barley, annual cereal plant (Hordeum vulgare and sometimes other species) of the family Poaceae (grass family), cultivated by humans probably as early as any cereal. It was known to the ancient Greeks...

silicone

(Encyclopedia)silicone, polymer in which atoms of silicon and oxygen alternate in a chain; various organic radicals, such as the methyl group, CH3, are bound to the silicon atoms. Silicones, which are unusually sta...

Campbell, William Cecil

(Encyclopedia)Campbell, William Cecil, 1930–, Irish-American biologist and parasitologist, b. Derry, Northern Ireland, Ph.D. Univ. of Wisconsin–Madison, 1957. He became a U.S. citizen in 1962. From 1957 to 1990...