A padded glove used for handling hot cookware from an oven. Wasei-eigo from English 'oven mitten'; the Japanese term is a single concept covering both mitt and glove styles.
wasei-eigo (Japanese-coined English), from oven mitten
See also: 鍋つかみ
I used an oven mitt to take out the hot baking sheet.
I bought a new oven mitt.