/ Dictionary / Index T territorialism: Meaning and Definition of Find definitions for: ter•ri•to•ri•al•ism Pronunciation: (ter"i-tôr'ē-u-liz"um, -tōr'-), [key] — n. a principle or system that gives predominance to the landed classes. Also calleda theory of church policy according to which the supreme ecclesiastical authority is vested in the civil power. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. territorial court territoriality Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language