gloom vs ambience

gloom and ambience both are nouns.

Word	Noun	Adjective	Verb	Adverb
gloom	Yes	No	No	No
ambience	Yes	No	No	No

As nouns, ambience is a hypernym of gloom; that is, ambience is a word with a broader meaning than gloom:

Other hypernyms of gloom include ambiance, atmosphere.

gloom (noun)	ambience (noun)
a feeling of melancholy apprehension	the atmosphere of an environment
a state of partial or total darkness	a particular environment or surrounding influence
an atmosphere of depression and melancholy