Synonyms for Blab:

n.

lay something bare, reveal, inform, tell, divulge, leak, give away, disclose, let (it) slip, offload. gab. unveil, uncover, discover, show, betray, expose, let out. words, rumor, noise, whisper. blab (noun)
tattle, sing, blabber, blab out, maunder, peach, clack, gabble, palaver, babble out, gibber, talk, piffle, babble, chatter, tittle-tattle, prattle, twaddle, prate.
empty talk (noun)
palaver.

v.

gossip (verb)
divulge, give away, babble, gabble, tattle, chatter, gab, let out, tell, betray, peach, prattle, reveal, disclose.

Other synonyms:

reveal. inform, divulge. unveil, discover. uncover, betray. expose. tell. blurt
let out.
gabble
gabble.
reveal
give away.
Other relevant words:
unveil, divulge, babble, gab, disclose, give away, rumor, discover, uncover, reveal, let out, leak, noise, expose, inform, betray, whisper, tell.