A marine bearing weapons (4)

I believe the answer is:

arms

'weapons' is the definition.
('arm' can be a synonym of 'weapon')

'a marine bearing' is the wordplay.
'marine' becomes 'rm'.
'bearing' becomes 's'.
'a'+'rm'+'s'='ARMS'

(Other definitions for arms that I've seen before include "Arsenal's items?" , "bombs and guns etc" , "What the Venus de Milo lacks" , "George Bernard Shaw play '. . . . and the Man'" , "See 11" .)

I've seen this clue in The Telegraph.

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