slap ‧ stick /ˈslæpˌstɪk/ BrE AmE noun [uncountable]
[ Date: 1900-2000 ; Origin: slapstick 'two joined sticks used in the theater for making slapping sounds' (19-20 centuries) ]
humorous acting in which the performers fall over, throw things at each other etc:
a slapstick comedy