/ Dictionary / Index T thy: Meaning and Definition of Find definitions for: thy Pronunciation: (ī), [key] — pron. the possessive case of thou (used as an attributive adjective before a noun beginning with a consonant sound):Cf. thy table. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Thwing Thyatira Related Content Daily Word Quiz: cygnet Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language