Blab

(v.) To utter or tell unnecessarily, or in a thoughtless manner; to publish (secrets or trifles) without reserve or discretion.

Blab - Other Definitions

(v.) To utter or tell unnecessarily, or in a thoughtless manner; to publish (secrets or trifles) without reserve or discretion.
(v. i.) To talk thoughtlessly or without discretion; to tattle; to tell tales.
(n.) One who blabs; a babbler; a telltale.