Clack (?), v. i. [imp. & p. p.Clacked (?); p. pr. & vb. n.Clacking.] [Prob. of imitative origin; cf. F. claquer to clap, crack, D. klakken, MHG. klac crack, Ir. clagaim I make a noise, ring. Cf. Clack, n., Clatter, Click.] 1. To make a sudden, sharp noise, or a succesion of such noises, as by striking an object, or by collision of parts; to rattle; to click.
We heard Mr.Hodson's whip clacking on the ahoulders of the poor little wretches.
Thackeray.
2. To utter words rapidly and continually, or with abruptness; to let the tongue run.