stow it

If someone tells you to stow it, they mean to say that you should be quiet or shut up. It is a slightly impolite way to tell someone to be quiet and stop talking. By saying stow it, they are saying to stop what they are currently doing and stow it away for later which is another way to say to save it for later. By referring to someone speaking, it means to stop talking and save this conversation for a later time.