/ Dictionary / Index Q quasquicentennial: Meaning and Definition of Find definitions for: quas•qui•cen•ten•ni•al Pronunciation: (kwos"kwi-sen-ten'ē-ul), [key] — adj. pertaining to or marking a period of 125 years. —n. a 125th anniversary. a celebration marking such an anniversary. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. quasi-stellar radio source quass Related Content Daily Word Quiz: immense Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language