Denshi Jisho — Online Japanese dictionary

轟音 ごうおん thunderous roar; roaring sound
Noun 
轟々 ごうごう 1:
2: (Usually written using kana alone) thunderous; rumbling; (Adverb taking the 'to' particle) thunderously; rumblingly
Na-adjective, Noun 
轟轟 ごうごう 1:
2: (Usually written using kana alone) thunderous; rumbling; (Adverb taking the 'to' particle) thunderously; rumblingly
Na-adjective, Noun 
轟然 ごうぜん roaring
Noun, Taru-adjective, Adverb taking the 'to' particle 
轟沈 ごうちん sinking a ship instantly
Noun, Suru verb 
轟き とどろき 1: roar; peal; rumble; booming;
2: beating; pounding; throbbing
Noun 
轟く とどろく 1: to roar;
2: to be well-known; to be famous;
3: to palpitate; to throb
Godan verb with ku ending, Intransitive verb 
轟かす とどろかす to make a thundering sound; to make roar
Godan verb with su ending, Transitive verb 
轟々 とどろとどろ thunderously; rumblingly
Adverb taking the 'to' particle 
轟轟 とどろとどろ thunderously; rumblingly
Adverb taking the 'to' particle 

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