Blab \Blab\ (bl[a^]b), v. t. [imp. & p. p. {Blabbed} (bl[a^]bd); p. pr. & vb. n. {Blabbing}.] [Cf. OE. blaberen, or Dan. blabbre, G. plappern, Gael. blabaran a stammerer; prob. of imitative origin. Cf. also {Blubber}, v.] To utter or tell unnecessarily, or in a thoughtless manner; to publish (secrets or trifles) without reserve or discretion; -- sometimes used with out. --Udall.
And yonder a vile physician blabbing The case of his patient. --Tennyson.
Blab \Blab\, v. i. To talk thoughtlessly or without discretion; to tattle; to tell tales.
She must burst or blab. --Dryden.
Blab \Blab\, n. [OE. blabbe.] One who blabs; a babbler; a telltale. ``Avoided as a blab.'' --Milton.
For who will open himself to a blab or a babbler. --Bacon.