Etymology
Advertisement
dither (v.)

1640s, "to quake, tremble," phonetic variant of Middle English didderen (late 14c.), which is of uncertain origin. The sense of "vacillate in opinion, be indecisive" is from 1908. Related: Dithered; dithering.

Related entries & more 
Advertisement
dodder (v.)

"to shake, tremble," 1610s, perhaps a variant of dadder, from Middle English daderen "to quake, tremble" (mid-14c.) a frequentative formation on a pattern similar to totter, patter, etc. Wedgwood points to a large group of similar words signifying motion to and fro, including dither, diddle, dandle, toddle, doddle ("shake the head," 1650s). Related: Doddered; doddering.

Related entries & more