quack vs let out

quack is a noun but let out is not a noun.

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

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

Other hypernyms of quack include emit, let loose, utter.

quack (noun)	let out (noun)
the harsh sound of a duck
an untrained person who pretends to be a physician and who dispenses medical advice

quack (adjective)	let out (adjective)
medically unqualified

quack (verb)	let out (verb)
act as a medical quack or a charlatan	make (clothes) larger
utter quacking noises	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