/ Dictionary / Index A alpha: Meaning and Definition of Find definitions for: al•pha Pronunciation: (al'fu), [key] — n. the first letter of the Greek alphabet (A, &agr;). the vowel sound represented by this letter. the first; beginning. (cap.)used to designate the brightest star in a constellation. one of two or more isomeric compounds. the first in a series of related items: frequently used in chemistry and physics. a mark or grade corresponding to an A. Cf. beta (def. 8),(def. 9). —adj. (esp. of animals) having the highest rank of its sex in a dominance hierarchy: the alpha female. pertaining or linked to the carbon atom closest to a particular group in an organic molecule. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: alpha (Thesaurus) alpestrine alpha-adrenergic Related Content Daily Word Quiz: immense Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language