/ Dictionary / Index S spiroid: Meaning and Definition of Find definitions for: spi•roid Pronunciation: (spī'roid), [key] — adj. more or less spiral; resembling a spiral. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. spirogyra spirometer Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language