Silly mugs full of self-satisfaction (4)

I believe the answer is:

smug

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'silly mugs full of self-satisfaction' is the definition.
I can't judge whether this definition defines the answer.

'silly mugs' is the wordplay.
'silly' indicates anagramming the letters.
'mugs' anagrammed gives 'SMUG'.

Can you help me to learn more?

(Other definitions for smug that I've seen before include "Spruce" , "Self-satisfied, complacent" , "Steal" , "Self-satisfied, stuffy" , "Conceited and self-satisfied" .)

I've seen this clue in the Evening Standard.

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