blabbing
blab-bing
verb
Revealing secrets or private information carelessly, or talking excessively and indiscreetly.
"Stop blabbing about our holiday plans!"
Thesaurus
Synonyms: tattle, gabble, prate, gibber, maunder, clack, tittle-tattle, palaver, blabber, twaddle, blab, prattle
Antonyms: keep one's mouth shut, keep quiet, shut one's mouth