facepiece; face mask part
Technical term for the part of a respirator, gas mask, or similar device that covers the face. Not a general word for mask.
The facepiece of this gas mask is made of silicone.
Please check that the facepiece fits snugly against your face.
Compound of 面 (めん, 'face') and 体 (たい, 'body'), literally 'face body'. The exact historical derivation is uncertain, but the term is used in modern technical contexts for the face-covering part of protective equipment.