noun
thunderous roar; roaring sound
Describes an overwhelmingly loud, deep, rumbling sound, such as an explosion, jet engine, or crashing waterfall.
ジェット機の轟音が空港中に響き渡った。
The thunderous roar of the jet echoed throughout the airport.
滝の轟音で会話が聞こえなかった。
We couldn't hear each other over the roaring sound of the waterfall.
爆音 specifically refers to an explosive sound or the roar of an engine, while 轟音 is a more general term for any deep, rumbling, thunderous noise.
Compound of 轟 (ごう, 'thunderous', 'roaring') and 音 (おん, 'sound'). The kanji 轟 is composed of three 車 (car) radicals, symbolizing the rumbling of many wheels.