/ Dictionary / Index V vital capacity: Meaning and Definition of Find definitions for: vi'tal capac'ity Pronunciation: [key] — Physiol. Physiol. the greatest amount of air that can be forced from the lungs after maximum inhalation. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. vital vital force Related Content Daily Word Quiz: penurious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language