Definition of quad
(Entry 1 of 8)
quad
noun (2)Definition of quad (Entry 2 of 8)
: a type-metal space that is one en or more in width
quad
verbquadded; quadding
Definition of quad (Entry 3 of 8)
: to fill out (something, such as a typeset line) with blank space
quad
noun (3) plural quads
Definition of quad (Entry 4 of 8)
quad
adjectiveDefinition of quad (Entry 5 of 8)
1 : having or composed of four items or elements : quadruple sense 1 The F/A-18 flight-control system … is characterized by quad redundancy, which means that there are essentially four levels of sensing and actuation for each control surface. — McGraw-Hill Yearbook Of Science And Technology Quad skates are roller skates that have four wheels arranged in two rows, while inline skates have them in one line.— Jenee Osterheldt
2 : quadraphonic Domestic quad listening needs two additional loudspeakers over stereo, and two more amplifiers, plus the black box which allocates some of the sounds to the rear left/right, and others to the front left/right.— George Steedman
quad
noun (4)Definition of quad (Entry 6 of 8)
: quadraphonic sound
quad
noun (5)Definition of quad (Entry 7 of 8)
: a unit of energy equal to one quadrillion British thermal units
quad
noun (6) plural quads
Definition of quad (Entry 8 of 8)
informal
: the greater extensor muscle of the front of the thigh that is divided into four parts : quadriceps —usually plural"Usually after a heptathlon I can tell if I'm not going to do well jumping. My quads get tired."— Jackie Joyner-KerseeDick Williams, Seattle manager, on shortstop Spike Owen's injured quads: "I never had any quads when I played." — Sports Illustrated
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Time Traveler for quad
The first known use of quad was in 1820
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