/ Dictionary / Index A alpha rhythm: Meaning and Definition of Find definitions for: al'pha rhythm" Pronunciation: [key] a pattern of slow brain wavesin normal persons at rest with closed eyes, thought by some to be associated with an alert but daydreaming mind. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. alpha receptor alpha-stannic acid Related Content Daily Word Quiz: laudable Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language