Mug is an insult. Mainly an English term, so I'd appreciate it if my yank friends wouldnt vote a thumbs down just because you've never heard it before, awrite? Good, ya mug.
Its hard to give a precise definition, but basically a mug is a naive or easily cheated person, an idiot, or just somebody you dont like
Dodgy used car salesman: "The punters are all mugs!"
Me: "You mug!"
The Urban Dictionary Mug
One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.
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