mitt; baseball glove
Specifically a baseball catcher's or first baseman's mitt, as opposed to a fielder's glove (グラブ).
キャッチャーは新しいミットを使っている。
The catcher is using a new mitt.
The catcher put on his mitt and got ready.
一塁手は大きなミットをはめている。
The first baseman is wearing a large mitt.
He firmly caught the fast ball with his mitt.
first baseman's mitt
catcher's mitt
Borrowed from English 'mitt', short for 'mitten'.