单词dental-dam
n.: 橡皮障（牙医用的牙齿阻隔膜）；（性交时用的）口腔保护膜网络: 牙科用的阻隔膜；牙科用橡皮布；牙用橡胶障
橡皮障（牙医用的牙齿阻隔膜）:
a small rubber sheet used by dentists to keep a tooth separate from the other teeth
（性交时用的）口腔保护膜；口交保险膜:
a small rubber sheet used to protect the mouth during sex