Answer: thwack

AnswerCrossword Clue
THWACKSound of a hit
THWACKHit with a paddle
THWACKHitting sound
THWACKBang.
THWACKHeavy blow.
THWACKWallop
THWACKImpact noise
THWACKSound of a sharp blow
THWACKPummel
THWACKSharp blow
THWACKSmack with a book, e.g.
THWACKMega-hit?
thwackto strike hard with something flat
thwacksharp blow with something flat
thwackto strike with something flat