Wiktionary
smash down
vb. (context transitive English) To cause to fall down and break by hitting it hard.
Usage examples of "smash down".
Once or twice the roped kegs bobbed and bounced so energetically that Jonathan feared they would smash down onto a rock beneath the surface and break to bits.
His left hand, still gripping the torch, as raised high to smash down on the unprotected nape of susan's neck.
His crushing iron bear had had to loose him completely to smash down three of the mechanical hound-cats at once.