Being in a state of indecisive agitation. The OED defines dither as “to tremble, quake, quiver, thrill” and cites its earliest use as 1649, just slightly before computer graphics became important. Dithering is often applied to little old ladies trying to decide whether to go for the Earl Grey or the Oolong. It also describes a boss well when you present a suggestion to him that he’s not sure his superiors will like.

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