/ Dictionary / Index H hydroformylation: Meaning and Definition of Find definitions for: hy•dro•for•myl•a•tion Pronunciation: (hī"dru-fôr"mu-lā'shun), [key] — n. the addition of a hydrogen atom and the formyl group to a double bond of a hydrocarbon by reaction with a mixture of carbon monoxide and hydrogen in the presence of a catalyst. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. hydroforming hydrofracturing Related Content Daily Word Quiz: diligent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language