noun
mushroom cloud
Specifically refers to the mushroom-shaped cloud from a nuclear explosion or large blast.
広島にキノコ雲が立ち上った。
A mushroom cloud rose over Hiroshima.
核実験で巨大なキノコ雲が発生した。
A huge mushroom cloud was produced by the nuclear test.
入道雲 is a towering cumulonimbus cloud, not a mushroom cloud from an explosion.
Compound of キノコ (mushroom) and 雲 (cloud), from the resemblance to a mushroom cap and stem.