overboard

o·ver·board /ˈəuvəbɔːd US ˈouvərbɔːrd/ adv
over the side of a ship or boat into the water
One of the crew fell overboard and drowned.
Man overboard! (=said when someone falls off a boat)
go overboard
to do or say something that is too extreme for a particular situation
I hope politicians will not go overboard in trying to control the press.
throw sth overboard
to get rid of an idea, system etc that is considered to be useless or unnecessary