/ Dictionary / Index S sea walnut: Meaning and Definition of Find definitions for: sea' wal"nut Pronunciation: [key] a comb jelly, as of the genus Mnemiopsis, shaped like a walnut. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. sea wall seawan Related Content Daily Word Quiz: pristine Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language