Disturbed wild gelding (7)

I believe the answer is:

niggled

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'disturbed' is the definition.
The definition and answer can be both to do with human feelings as well as being past participle verbs.
Maybe there's an association between them I don't understand?

'wild gelding' is the wordplay.
'wild' is an anagram indicator.
'gelding' anagrammed gives 'NIGGLED'.

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I've seen this clue in The Sun.

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