A curious sort of plant (4)

I believe the answer is:

arum

'sort of plant' is the definition.

'a curious' is the wordplay.
'curious' becomes 'rum' ('rum' can be a synonym of 'curious').
'a'+'rum'='ARUM'

(Other definitions for arum that I've seen before include "A spirit for a lily" , "Perennial" , "Cuckoo-pint" , "Eg, cuckoo pint" , "plant with a white spathe" .)

I've seen this clue in The Telegraph.

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