also: ほさき
noun
flames; flame tips; forefront of fire
Refers to the visible flames themselves, especially the tips or leading edge of a fire. Often used in contexts like firefighting or describing a blaze.
火先が天井に届きそうだった。
The flames were about to reach the ceiling.
消防士が火先に向かって放水した。
The firefighters sprayed water toward the forefront of the fire.
炎 is the general word for 'flame' or 'blaze'. 火先 specifically emphasizes the tips or leading edge of flames, often in a dynamic or dangerous context.
Compound of 火 (hi, 'fire') and 先 (saki, 'tip' or 'front'), with rendaku voicing of saki to zaki. The reading ほさき uses the older combining form ほ for fire.