/ Dictionary / Index S sealed book: Meaning and Definition of Find definitions for: sealed' book' Pronunciation: [key] something beyond understanding and therefore unknown. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. sealed-beam headlight sealed orders Related Content Daily Word Quiz: effervescent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language