spill the beans vs let out

spill the beans and let out both are verbs.

Word	Noun	Adjective	Verb	Adverb
spill the beans	No	No	Yes	No
let out	No	No	Yes	No

As verbs, let out is a hypernym of spill the beans; that is, let out is a word with a broader meaning than spill the beans:

spill the beans: divulge confidential information or secrets
let out: 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 hypernyms of spill the beans include break, bring out, disclose, discover, divulge, expose, give away, let on, reveal, uncover, unwrap.

spill the beans (verb)	let out (verb)
divulge confidential information or secrets	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
	express audibly; utter sounds (not necessarily words)
	bring out of a specific state