Columbia Encyclopedia

Search results

500 results found

eclecticism, in philosophy

(Encyclopedia)eclecticism ĭklĕkˈtĭsĭzˌəm [key] [Gr. eklektikos=to choose], in philosophy, the selection of elements from different systems of thought, without regard to possible contradictions between the sy...

antidiuretic hormone

(Encyclopedia)antidiuretic hormone ănˌtēdīyo͞orĕtˈĭk [key], polypeptide hormone secreted by the posterior pituitary gland. Its principal action is to regulate the amount of water excreted by the kidneys. An...

sublimation, in chemistry

(Encyclopedia)sublimation sŭblĭmāˈshən [key], change of a solid substance directly to a vapor without first passing through the liquid state. The term is also used to describe the reverse process of the gas ch...

columbine, in botany

(Encyclopedia)columbine kŏlˈəmbīn [key], any plant of the genus Aquilegia, temperate-zone perennials of the family Ranunculaceae (buttercup family), popular both as wildflowers and as garden flowers. Columbines...

earth, in chemistry

(Encyclopedia)earth, in chemistry, metallic oxide not readily reducible by chemical means, e.g., alkaline earths, rare earths, and alumina. The name is also applied to certain absorbent clays, e.g., fuller's earth,...

Rothman, James Edward

(Encyclopedia)Rothman, James Edward, 1950–, American cell physiologist, b. Haverhill, Mass., Ph.D. Harvard, 1976. Rothman was a professor at Stanford from 1978 to 1988 and at Princeton from 1988 to 1991. He taugh...

Schally, Andrew V.

(Encyclopedia)Schally, Andrew V., 1926–, American endocrinologist, b. Wilno, Poland (now Vilnius, Lithuania), as Andrzej Viktor Schally, grad. McGill Univ. (Ph.D., 1957). He spent most of his career at Tulane Uni...

corona, in astronomy

(Encyclopedia)corona, luminous envelope surrounding the sun, outside the chromosphere. Its density is less than one billionth that of the earth's atmosphere. The corona is visible only at the time of totality durin...

phase, in astronomy

(Encyclopedia)CE5 Phases of the moon phase, in astronomy, the measure of how much of the illuminated surface of a planet or satellite can be seen from a point at a distance from that body; the term is most ofte...

gingivitis

(Encyclopedia)gingivitis jĭnˌjəvīˈtĭs [key], inflammation of the gums. It may be acute, subacute, chronic, or recurrent. The gums usually become red, swollen, and spongy, and bleed easily. Chronic gingivitis ...