One story exceptional about special display vessel kept in a church (9)

I believe the answer is:

ostensory

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'display vessel kept in a church' is the definition.
I can't tell whether this definition defines the answer.

'one story exceptional about special' is the wordplay.
'exceptional' indicates an anagram.
'about' is an insertion indicator.
'special' becomes 'S' (common abbreviation as in Special Air Service).
'one'+'story'='onestory'
'onestory' with letters rearranged gives 'otensory'.
'otensory' placed around 's' is 'OSTENSORY'.

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I've seen this clue in The Hindu.

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