/ Dictionary / Index V visible spectrum: Meaning and Definition of Find definitions for: vis'ible spec'trum Pronunciation: [key] — Physics. Physics. the range of wavelengths of electromagnetic radiation that is normally visible, from 380 to 760 nm. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. visible horizon visible speech Related Content Daily Word Quiz: divulge Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language