/ Dictionary / Index A adventive: Meaning and Definition of Find definitions for: ad•ven•tive Pronunciation: (ad-ven'tiv), [key] — Bot., Zool. Bot.,Zool. —adj. not native and usually not yet well established, as exotic plants or animals. —n. an adventive plant or animal. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: adventive (Thesaurus) adventitious Advent Sunday Related Content Daily Word Quiz: endear Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language