/ Dictionary / Index S synclastic: Meaning and Definition of Find definitions for: syn•clas•tic Pronunciation: (sin-klas'tik, sing-), [key] — adj. Math. (of a surface) having principal curvatures of similar sign at a given point. Cf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. synchro unit synclinal Related Content Daily Word Quiz: fidelity Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language