/ Dictionary / Index S sea mouse: Meaning and Definition of Find definitions for: sea' mouse" Pronunciation: [key] any of several large, marine annelids of the genus Aphrodite and related genera, having a covering of long, fine, hairlike setae. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. seamount seamster Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language