the human face (`kisser' and `smiler' and `mug' are informal terms for `face' and `phiz' is British)
"He turned around to show off his mug to the camera."
with handle and usually cylindrical
"She poured hot coffee into her ceramic mug to enjoy it while reading by the window."
A large cup for hot liquids, usually having a handle and used without a saucer.
"That guy is as stupid as a mug when it comes to fixing his own computer."
Motherfucker (usually in similes, e.g. "like a mug" or "as a mug")
In plain English: A mug is an open cup with handles that you use to drink hot liquids from.
"He carefully washed his favorite ceramic mug before putting coffee in it."
Usage: Use "mug" to refer specifically to a sturdy drinking vessel with a handle that is typically too tall or wide to fit on a standard table setting. Unlike smaller cups designed for tea served with a saucer, mugs are commonly associated with coffee and casual dining environments.
rob at gunpoint or with the threat of violence
"I was mugged in the streets of New York last night"
To strike in the face.
"The boxer was knocked down when his opponent mug him with a heavy right hook to the jaw."
Easily fooled, gullible.
"The new employee was so easily fooled that he fell for every trickster's scam without suspicion."
The word "mug" entered early 16th-century Scots and northern English from an uncertain source, possibly borrowing from North Germanic or Low German terms for a drinking vessel. While its exact origin remains unknown, it may be related to Old Norse words meaning a heap of grain rather than the cup itself.