ski mask; balaclava
A close-fitting head covering that leaves only the eyes (and sometimes mouth) exposed, used for warmth, disguise, or sports.
The criminal broke into the bank wearing a ski mask.
At the ski resort, a balaclava helps keep you warm.
Compound of 目出し (めだし, 'eye-exposing') + 帽 (ぼう, 'hat/cap'). The exact historical derivation is uncertain, but the spelling is conventionally associated with the meaning.