/ Dictionary / Index O optical fiber: Meaning and Definition of Find definitions for: op'tical fi'ber Pronunciation: [key] a very thin, flexible glass or plastic strand along which large quantities of information can be transmitted in the form of light pulses: used in telecommunications, medicine, and other fields. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. optical effects optical glass Related Content Daily Word Quiz: languid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language