flutter (v.)
Old English floterian "to flutter (of birds), to fly before, flicker, float to and fro, be tossed by waves," frequentative of flotian "to float" (see float (v.)). Meaning "throw (someone) into confusion" is from 1660s. Related: Fluttered; fluttering. As a noun, "quick, irregular motion," from 1640s; meaning "state of excitement" is 1740s. Flutterpate "flighty person" is from 1894.