/ Dictionary / Index O octadecanoic acid: Meaning and Definition of Find definitions for: oc'ta•dec•a•no'ic ac'id Pronunciation: (ok'tu-dek"u-nō'ik, ok"-), [key] — Chem. Chem. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. octad octagon Related Content Daily Word Quiz: fabricate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language