/ Dictionary / Index B block signal: Meaning and Definition of Find definitions for: block' sig"nal Pronunciation: [key] a fixed railroad signal governing the movements of trains entering and using a given section of track. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. block print block system 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