E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
A talkative person. The Germans have Plaudertasche (chatterbag). Shakespeare speaks of the clack-dish. His use was to put a ducat in her clack-dish (Measure for Measure, iii. 2)i.e. the box or dish used by beggars for collecting alms, which the holder clatters to attract attention. We find also chatter-basket in old writers, referring to the childs rattle.