A nymph puts a spell on one (5)

I believe the answer is:

houri

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'a nymph' is the definition.
(I know that nymph can be written as houri)

'a spell on one' is the wordplay.
'a spell on' becomes 'hour' (I can't explain this - if you can you should give a lot more credence to this answer).
'one' becomes 'I' (Roman numeral).
'hour'+'i'='HOURI'

'puts' is the link.

Can you help me to learn more?

(Other definitions for houri that I've seen before include "Young beautiful woman of the Moslem Paradise" , "Voluptuous female" , "Beautiful female" , "Alluring woman or nymph in Muslim paradise" , "Alluring female" .)

I've seen this clue in The Globe and Mail and The Guardian.

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