/ Dictionary / Index S Semënov: Meaning and Definition of Find definitions for: Se•më•nov Pronunciation: (sim-yô'nuf Russ. syi-myô'nuf&hasp), [key] born 1896, Russian chemist: Nobel prize 1956. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. semen semester Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language