/ Dictionary / Index A adenine: Meaning and Definition of Find definitions for: ad•e•nine Pronunciation: (ad'n-in, -ēn", -īn"), [key] — n. a purine base, CHN, one of the fundamental components of nucleic acids, as DNA, in which it forms a base pair with thymine, and RNA, in which it pairs with uracil. Symbol: A Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: adenine (Thesaurus) Adeni adenitis Related Content Daily Word Quiz: penchant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language