/ Dictionary / Index A alternation of generations: Meaning and Definition of Find definitions for: alterna'tion of genera'tions Pronunciation: [key] — Biol. Biol. the alternation in an organism's life cycle of dissimilar reproductive forms, esp. the alternation of sexual with asexual reproduction. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. alternation alternative Related Content Daily Word Quiz: resilient Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language