A mug is a large deep cup with straight sides and a handle, used for hot drinks. He spooned instant coffee into two of the mugs. A mug of something is the amount of it contained in a mug. He had been drinking mugs of coffee to keep himself awake
A mug is a handled drinking vessel which does not have a lid Many mugs, but not all, can be called unlidded steins, if they were supposed to have a lid
/mug/ (n): 1 An abbreviation for "My Undergraduate Group" A MUG consists of one MUG Leader and ten first year students 2 A drinking vessel commonly used to hold yummy root beer floats at the Main Event
A mug shot or a small photo of someone If someone says, "get me a mug," don't come back with coffee
disapproval If you say that an activity is a mug's game, you mean that it is not worth doing because it does not give the person who is doing it any benefit or satisfaction. I used to be a very heavy gambler, but not any more. It's a mug's game
disapproval If you say that someone is a mug, you mean that they are stupid and easily deceived by other people. He's a mug as far as women are concerned