His meanness upsets me sir (5)

I believe the answer is:

miser

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'his meanness' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.

'upsets me sir' is the wordplay.
'upsets' is an anagram indicator.
'me'+'sir'='mesir'
'mesir' with letters rearranged gives 'MISER'.

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(Other definitions for miser that I've seen before include "Stingy person like Scrooge" , "One such as Scrooge" , "One doesn't spend much" , "Person who hoards money" , "not a spendthrift" .)

I've seen this clue in the Evening Standard.

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