/ Dictionary / Index A air-hardening: Meaning and Definition of Find definitions for: air-hard•en•ing Pronunciation: (âr'här"dn-ing), [key] — adj. Metall. noting any metal, esp. alloy steel, that can be hardened from above its transformation point by cooling in air. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. air harbor airhead Related Content Daily Word Quiz: reiterate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language