That girl's exercise with little jerk indicative of a skin disease (8)

I believe the answer is:

herpetic

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'indicative of a skin disease' is the definition.
The definition suggests an adjective which matches the answer.

'that girl's exercise with little jerk' is the wordplay.
'that girl' becomes 'her' ('her' refers to a girl or woman).
'exercise' becomes 'pe' (Physical Education).
'with' is a charade indicator (letters next to each other).
'little jerk' becomes 'tic' (jerking movement by the body).
'her'+'pe'+'tic'='HERPETIC'

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

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