Detective, seeing that curtailed course, is put off (10)

I believe the answer is:

disincline

'is put off' is the definition.
(thesaurus)

'detective seeing that curtailed course' is the wordplay.
'detective' becomes 'di' (Detective Inspector abbreviation).
'seeing that' becomes 'since' (both can mean 'when considering...').
'curtailed' means to remove the last letter.
'course' becomes 'line' (synonyms).
'since' with its last letter taken off is 'sinc'.
'di'+'sinc'+'line'='DISINCLINE'

I've seen this clue in The Independent.

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