/ Dictionary / Index S semidaily: Meaning and Definition of Find definitions for: sem•i•dai•ly Pronunciation: (sem"ē-dā'lē, sem"ī-), [key] — adj., adv. twice daily. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. semicylinder semidarkness Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language