Emily Dickinson Lexicon

BLUN'DER, v.i. [This word seems to be allied to the Gr. πλαναω, to err; and to flounder. The sense of the latter is to move with sudden jerks, and irregular motions. In Dan. blunder is to wink, twinkle or dissemble; allied to Fr. loin.]

1. To mistake grossly; to err widely or stupidly. – Johnson.
2. To move without direction, or steady guidance; to plunge at an object; to move, speak or write with sudden and blind precipitance; as, to blunder upon a reason; to blunder round a meaning. – Pope.
3. To stumble, as a horse; a common use of word.