adverb, adverb taking the 'to' particle
Mimetic word for a low, continuous buzzing or humming sound, such as an insect or motor.
蚊が耳の近くでぶんぶん飛んでいる。
A mosquito is buzzing near my ear.
冷蔵庫がぶんぶんと音を立てている。
The refrigerator is humming.
adverb, adverb taking the 'to' particle
shake vigorously; shaking
Describes shaking something with force or energy, often with a continuous motion.
犬が体をぶんぶん振って水を飛ばした。
The dog shook itself vigorously and splashed water everywhere.
彼は首をぶんぶんと横に振った。
He shook his head vigorously from side to side.
Onomatopoeic or mimetic word; the exact derivation is uncertain.