a swinging or sliding barrier that will close the entrance to a room or building or vehicle
the entrance (the space in a wall) through which you enter or leave a room or building; the space that a door can close
drain consisting of a U-shaped section of drainpipe that holds liquid and so prevents a return flow of sewer gas
something (often something deceptively attractive) that catches you unawares
a device to hurl clay pigeons into the air for trapshooters
the act of concealing yourself and lying in wait to attack by surprise
