Nominally a loud leftist (4)

I believe the answer is:

fred

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'nominally a' is the definition.
I can't tell whether this definition defines the answer.

'loud leftist' is the wordplay.
'loud' becomes 'f' (short for forte - 'loud' in music).
'leftist' becomes 'red' (red can informally mean communist).
'f'+'red'='FRED'

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(Other definitions for fred that I've seen before include "- - Hoyle, astronomer" , "Man" .)

I've seen this clue in the Evening Standard.

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