decollete vs low-cut

decollete and low-cut both are adjectives.

Word	Noun	Adjective	Verb	Adverb
decollete	No	Yes	No	No
low-cut	No	Yes	No	No

As adjectives, decollete and low-cut are synonyms defined as:

Other synonyms of decollete include low-necked.

decollete (adjective)	low-cut (adjective)
(of a garment) having a low-cut neckline	having a low-cut back
	(of a garment) having a low-cut neckline