ボーボー

ボーボー, ボウボウ, ぼうぼう, ぼーぼーbooboo

adverb

  1. vigorously (burning)
  2. furiously
  3. fiercely

Study it in Yanamino

Data from JMdict, KANJIDIC2 (EDRDG), KanjiVG, CC-CEDICT and Make Me a Hanzi. Sources and licences