let out vs let on

let out and let on both are verbs.

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

As verbs, let out and let on are synonyms defined as:

let out and 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

Other synonyms of let out include break, bring out, disclose, discover, divulge, expose, give away, reveal, uncover, unwrap.

let out (verb)	let on (verb)
make (clothes) larger	make known to the public information that was previously known only to a few people or that was meant to be kept a secret
make known to the public information that was previously known only to a few people or that was meant to be kept a secret
express audibly; utter sounds (not necessarily words)
bring out of a specific state