/ Dictionary / Index S smoothen: Meaning and Definition of Find definitions for: smooth•en Pronunciation: (sm'un), [key] — v.t., v.i. to make or become smooth. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: smoothen (Thesaurus) smooth dogfish smooth endoplasmic reticulum Related Content Daily Word Quiz: neologism Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language