/ Dictionary / Index A Achilles heel: Meaning and Definition of Find definitions for: Achil'les heel' Pronunciation: [key] a portion, spot, area, or the like, that is especially or solely vulnerable: His Achilles heel is his quick temper. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Achilles Achilles reflex Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language