Ship’s biscuit in tricky way (4,4)

I believe the answer is:

hard tack

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'ship's biscuit' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'tricky way' is the wordplay.
'tricky' becomes 'hard' (similar in meaning).
'way' becomes 'tack' (tack is a kind of way).
'hard'+'tack'='HARD-TACK'

'in' is the link.

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I've seen this clue in The Guardian.

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