Quad, Quadrat

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When used as a verb, quad means, in typography and typesetting, to space out the blank portion of a line to its full measure. See Quadding.

When used as a noun, quad means, in metal typography, a blank piece of metal—more formally called a quadrat—used to fill up a line of type, forcing the rest of the characters into a desired position on the line. Quads were used to set a line flush left, flush right, or centered.

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