/ Dictionary / Index O oil-immersion objective: Meaning and Definition of Find definitions for: oil'-im•mer•sion objec"tive Pronunciation: (oil'i-mûr"zhun, -shun), [key] — Optics. Optics. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. oil-harden oillet 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