Kyūjitai form of 火薬

(Buddhism) a fiery chariot that brings sinners to hell; by extension, a form of torture using this vehicle / a burning fire in the shape of a wheel / Short for 火車婆 (kasha-baba): a powerful, evil old hag

boiler / furnace

(Internet slang) Firefox (web browser)

a clock that tells time using the burning of sticks of incense or fuses

(mythology, Shinto, possibly archaic) a god of fire, another name for Kagutsuchi

(mythology) a phoenix, more specifically as in Western mythology

fireball / bolide; comet, shooting star

catch fire, be ignited

St. Elmo's fire (electrical discharge)