a device worn over the nose and mouth to prevent you from breathing in harmful substances, such as bacteria or pollution, or from breathing bacteria or viruses onto anyone else

Medical staff are required to wear protective gloves and face masks. 医务人员必须戴上防护手套和口罩。

a front part of a helmet (= a hard hat) worn in some sports, for example American football, that protects the face and mouth

In those days they played without face masks. 那时候，他们在比赛中是不戴面罩的。

a cream or a piece of thin material that is left on the face for some time and then removed, in order to make the skin look and feel better

This Honey Bio face mask contains seven secret herbs to cleanse and heal the skin. 这款蜂蜜生物面膜含有七种秘方草药，可清洁和修复肌肤。