Soldiers round a base (4)

I believe the answer is:

mean

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'base' is the definition.
('mean' can be a synonym of 'base')

'soldiers round a' is the wordplay.
'soldiers' becomes 'em' (I can't explain this - if you can you should believe this answer much more).
'round' is a reversal indicator.
'a' becomes 'an'.
'em' written backwards gives 'me'.
'me'+'an'='MEAN'

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(Other definitions for mean that I've seen before include "Intend - average - poor" , "Stingy in average way" , "Bad-tempered" , "Name for being stingy" , "Niggardly" .)

I've seen this clue in The Telegraph.

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