A ball (formal dance) in which the dancers wear masks or fancy dress

plural of oxygen mask

plural of gas mask

plural of diving mask

plural of death mask

A hard white hockey mask such as popularised by the character Jason Voorhees in the Friday the 13th films.

(medicine) Masklike facial expression, often noted in Parkinson's disease.

plural of facial mask

An application of mud, clay, etc. to the skin of the face for cosmetic purposes.

A facemask worn to catch droplets and aerosols, which contain bacteria and viruses. / A medical-grade mask worn during medical procedures.