chorus vs let loose

chorus is a noun but let loose is not a noun.

Word	Noun	Adjective	Verb	Adverb
chorus	Yes	No	Yes	No
let loose	No	No	Yes	No

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

Other hypernyms of chorus include emit, let out, utter.

chorus (noun)	let loose (noun)
the part of a song where a soloist is joined by a group of singers
any utterance produced simultaneously by a group
a group of people assembled to sing together
a body of dancers or singers who perform together
a company of actors who comment (by speaking or singing in unison) on the action in a classical Greek play

chorus (verb)	let loose (verb)
utter in unison	express audibly; utter sounds (not necessarily words)
sing in a choir	turn loose or free from restraint