Nuns sloped off in confusion (10)

I believe the answer is:

nonplussed

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'nuns sloped off in confusion' is the definition.
I can't tell whether this defines the answer.

'nuns sloped off' is the wordplay.
'off' is an anagram indicator.
'nuns'+'sloped'='nunssloped'
'nunssloped' anagrammed gives 'NONPLUSSED'.

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(Other definitions for nonplussed that I've seen before include "Threw" , "was confusing" , "Flummoxed" , "Surprised and confused" , "Confounded" .)

I've seen this clue in The Independent.

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