/ Dictionary / Index B beam splitter: Meaning and Definition of Find definitions for: beam' split"ter Pronunciation: [key] — Optics, Photog. Optics,Photog. a mirror or prism that divides a beam of light into two parts by reflecting a part of the beam, used in camera range finders. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. beam sea beam trawl Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language