Quad

wiktionary

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From Latin.

Clippings. 

Abbreviation

1785 Quads. pl, 1847 quads, verb 1876. From the abbreviation quad., for obsolete quadrat. Keyboard command is named for the verb sense.

etymonline

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quad

1820 as a shortening of quadrangle (n.) in the building-court sense (in this case "quadrangle of a college," Oxford student slang); also in old slang the quadrangle of a jail or prison, where prisoners take their exercise. By 1880 as short for the printer's quadrat (n.). By 1896 as "a quadricycle, a bicycle for four riders" (quadricycle is attested by 1879, quadruplet in this sense by 1893). As "one of four young at a single birth" by 1951 (in reference to armadillos), short for quadruplet; 1970 as a shortening of quadraphonic (adj.). Related: Quads.