Part-fracture? (8,5)

I believe the answer is:

hairline crack

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'part-fracture?' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'part-fracture?' is the wordplay.
'part' becomes 'hairline' (hairline is a kind of part).
'fracture?' becomes 'crack' (cracking is a kind of fracturing).
'hairline'+'crack'='HAIRLINE CRACK'

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

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