let on vs blab out

let on and blab out both are verbs.

Word	Noun	Adjective	Verb	Adverb
let on	No	No	Yes	No
blab out	No	No	Yes	No

As verbs, blab out is a hyponym of let on; that is, blab out is a word with a more specific, narrower meaning than let on:

let on: make known to the public information that was previously known only to a few people or that was meant to be kept a secret
blab out: divulge confidential information or secrets

let on (verb)	blab out (verb)
make known to the public information that was previously known only to a few people or that was meant to be kept a secret	divulge confidential information or secrets