| quadri-, quadra-, quad-, quadru- (Latin: four; a number used as a prefix).biquadrate: quadragenarian, quadragenary, quadragenarious: A person who is forty to forty-nine years old.
 quadragesima: quadragesimal: quadrangle: quadrangular: quadrant: quadrantal: quadraphonic: quadraphonically: quadraphonics: quadraphony: quadraplegic: quadrat: quadrate: quadratic: quadratics: quadrature: quadrennia (plural): quadrennial: quadrennially: quadrennium (singular): quadric: quadricentennial: quadriceps: quadricycle: quadrifid: quadrifoliate: quadrifurcation: quadrigamist: quadrigamy: quadrilateral: quadrilingual: quadrille: quadrillion: quadrinomial: quadripartite: quadriphonic: quadriphonics: quadriplegia: quadriplegic: quadrireme: quadrisect: quadrisyllable: quadrivalent: quadrivium: quadroon: quadrophonic: quadrumane: quadrumanous: quadrumvirate: quadruped: quadrupedal: quadruple: quadruplet: quadruplets: quadruplex: quadruplicate: quadruplication: quadruplicity: quadruply: |