noun
pyrocumulonimbus cloud
Rare technical term in meteorology for a cumulonimbus cloud formed by a large fire or volcanic eruption.
大規模な山火事で火災積乱雲が発生した。
A pyrocumulonimbus cloud formed from the large-scale wildfire.
Compound of 火災 (kasai, 'fire, conflagration') + 積乱雲 (sekiran'un, 'cumulonimbus cloud').