Breadcrumb Home > Dictionary Cite Meaning of orthodox sleep Find definitions for: or'thodox sleep' Pronunciation: [key] — Physiol. Physiol. dreamless sleep, characterized by a slow alpha rhythm of brain waves and no marked physiological changes. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Orthodox Judaism orthodoxy Related Content Daily Word Quiz: persiflage Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language