noun
embers; live charcoal
Refers to glowing, hot charcoal or embers, often in a traditional hearth or brazier. Not used for modern electric or gas heating.
囲炉裏の熾がまだ赤く光っている。
The embers in the sunken hearth are still glowing red.
熾を火鉢に移して部屋を暖めた。
We moved the live charcoal to the brazier to warm the room.
The reading おき is native Japanese. The kanji 熾 and 燠 both carry the meaning of burning embers, but their historical derivation is uncertain.