Answer: trebling

AnswerCrossword Clue
TREBLINGMultiplying in a way
TREBLINGIncreasing severalfold
TREBLINGIncreasing threefold
TREBLINGGetting bigger quickly
treblingthe treble part, voice, or instrument
treblingtriple
treblingof the highest musical pitch or range
treblingthe act of multiplying by three
treblingto triple