decolletage

• n. 袒胸露背的衣服

de-, 向下。-coll, 领子，词源同collar. 即衣领下的，低胸露肩的领。

decolletage (n.)

1894 (from 1883 as a French word in English), from French décolletage, from décolleté "low-necked" (see decollete).