/ Dictionary / Index L life science: Meaning and Definition of Find definitions for: life' sci'ence Pronunciation: [key] any science that deals with living organisms, their life processes, and their interrelationships, as biology, medicine, or ecology. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Lifesaving Service life sentence Related Content Daily Word Quiz: cur Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language