noun
hot sake
Refers to sake that has been warmed, typically to around 50°C. Common in colder months and at izakaya.
寒い日は熱燗がおいしい。
Hot sake is delicious on a cold day.
居酒屋で熱燗を頼んだ。
I ordered hot sake at the izakaya.
Compound of 熱 (あつ, 'hot') and 燗 (かん, 'warming sake'). The reading あつかん is a straightforward combination of the on'yomi of the kanji.