noun
kettle; teakettle
A pot or kettle for boiling water, typically used in the kitchen.
湯沸かしでお湯を沸かしてください。
Please boil water in the kettle.
やかん is a more common word for a kettle, often made of metal and used on a stove. 湯沸かし can refer to an electric kettle or a pot specifically for boiling water.
Compound of 湯 (yu, 'hot water') and 沸かし (wakashi, the noun form of 沸かす 'to boil').