/ Dictionary / Index S spheno-: Meaning and Definition of Find definitions for: spheno- Pronunciation: [key] a combining form meaning “wedge,” used in the formation of compound words: sphenography. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. sphenic sphenodon Related Content Daily Word Quiz: procrastinate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language