Look at the picture and try to guess the meaning of the idiom 'put a sock in it.'
Put a sock in it: a rude (impolite) way of telling someone to stop talking or be quiet (stop making a lot of noise).
You know what a sock is, right? It's the piece of clothing (usually made of knitted cotton, wool or silk) that you put on your feet (and can pull all the way up to your lower leg or knees) to stay warm and dry. You can see the man in the picture above has two socks in his mouth.
The "it" part of the phrase refers to someone's mouth. So the phrase means, put a sock in someone's mouth.
Well, that's going to make it difficult to talk or if someone does manage to talk it is going to muffle the sound (make it lower in volume). Think of a criminal who kidnaps someone and puts something in or over their mouth to keep them from yelling for help.
That's not a nice thing to do is it? So, remember also that this is a rude or impolite way to tell someone to be quiet. Please do not tell your boss, teacher or priest / pastor to put a sock in it! You may not want to say it to a stranger either. It's safe for friends and peers but they may not like hearing it. They will, however, understand that you are annoyed by their noise.
It's often used as a command (Put a sock in it!) or a request (Will you put a sock in it?).
A synonym of this phrase is simply: Shut up!
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