Mast features of garden weapons (8)

I believe the answer is:

yardarms

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'mast features' is the definition.
Although both the answer and definition are plural nouns, I don't understand how they can define each other.

'garden weapons' is the wordplay.
'garden' becomes 'yard' (I have seen 'American garden' mean 'yard' so perhaps 'garden' could also mean 'yard').
'weapons' becomes 'arms' ('arm' can be a synonym of 'weapon').
'yard'+'arms'='YARDARMS'

'of' acts as a link.

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I've seen this clue in the Sydney Morning Herald.

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