To hit/kick something (usually a ball) hard, especially in sport, e.g. football, pool. Not really for use in fight situations, e.g. you cant say "Twont that dude in the face"
Related to the word twat, e.g. to twat a ball
In playing pool - "Just twont it"
In playing football - "Just twont it"
In playing rugby - "Twont the motherfucking ball you cunting fuck nut" etc