/ Dictionary / Index T tertial: Meaning and Definition of Find definitions for: ter•tial Pronunciation: (tûr'shul), [key] — Ornith. Ornith. —adj. pertaining to any of a set of flight feathers situated on the basal segment of a bird's wing. —n. a tertial feather. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. terse tertian 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