'Blunder' definitions:

Definition of 'Blunder'

From: GCIDE

Blunder \Blun"der\, v. t.
1. To cause to blunder. [Obs.] "To blunder an adversary." --Ditton. [1913 Webster]
2. To do or treat in a blundering manner; to confuse. [1913 Webster]
He blunders and confounds all these together. --Stillingfleet. [1913 Webster]

From: GCIDE

Blunder \Blun"der\, n.
1. Confusion; disturbance. [Obs.] [1913 Webster]
2. A gross error or mistake, resulting from carelessness, stupidity, or culpable ignorance. [1913 Webster]
Syn: Blunder, Error, Mistake, Bull.
Usage: An error is a departure or deviation from that which is right or correct; as, an error of the press; an error of judgment. A mistake is the interchange or taking of one thing for another, through haste, inadvertence, etc.; as, a careless mistake. A blunder is a mistake or error of a gross kind. It supposes a person to flounder on in his course, from carelessness, ignorance, or stupidity. A bull is a verbal blunder containing a laughable incongruity of ideas. [1913 Webster]

From: GCIDE

Blunder \Blun"der\, v. i. [imp. & p. p. Blundered; p. pr. & vb. n. Blundering.] [OE. blunderen, blondren, to stir, confuse, blunder; perh. allied to blend to mix, to confound by mixture.]
1. To make a gross error or mistake; as, to blunder in writing or preparing a medical prescription. --Swift. [1913 Webster]
2. To move in an awkward, clumsy manner; to flounder and stumble. [1913 Webster]
I was never distinguished for address, and have often even blundered in making my bow. --Goldsmith. [1913 Webster]
Yet knows not how to find the uncertain place, And blunders on, and staggers every pace. --Dryden. [1913 Webster]
To blunder on. (a) To continue blundering. (b) To find or reach as if by an accident involving more or less stupidity, -- applied to something desirable; as, to blunder on a useful discovery. [1913 Webster]