dé·colle·té 
(d
ā′kôl-t
ā)
adj.1. Cut low at the neckline: a décolleté dress.
2. Wearing a garment that is low-cut or strapless.
[French, past participle of décolleter, to lower a neckline, uncover the neck : dé-, off (from Latin dē-; see DE-) + collet, collar (from Old French, diminutive of col, neck, collar, from Latin collum, neck; see kwel-1 in the Appendix of Indo-European roots).]