Décolletage
Décolletage (dā`ko`l'*tȧzh) , noun
[F. See Décolleté.]
1.
(Costume) The upper border or part of a low-cut (that is, décolleté) dress.
2.
The exposed upper parts of the breasts of a woman wearing a low-cut dress; as, transfixed by her stunning decolletage.
Also: Decolletage