spray gun vs applier

spray gun and applier both are nouns.

Word	Noun	Adjective	Verb	Adverb
spray gun	Yes	No	No	No
applier	Yes	No	No	No

As nouns, applier is a hypernym of spray gun; that is, applier is a word with a broader meaning than spray gun:

spray gun: an applicator resembling a gun for applying liquid substances (as paint) in the form of a spray
applier: a device for applying a substance

Other hypernyms of spray gun include applicator.

spray gun (noun)	applier (noun)
an applicator resembling a gun for applying liquid substances (as paint) in the form of a spray	a device for applying a substance
	a person who requests or seeks something such as assistance or employment or admission