/ Dictionary / Index I infirmity: Meaning and Definition of Find definitions for: in•fir•mi•ty Pronunciation: (in-fûr'mi-tē), [key] — pl. -ties a physical weakness or ailment: the infirmities of age. quality or state of being infirm; lack of strength. a moral weakness or failing. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: infirmity (Thesaurus) infirmary infix Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language