A love for indigo (4)

I believe the answer is:

anil

'indigo' is the definition.
(anil is a kind of indigo)

'a love' is the wordplay.
'love' becomes 'nil' (I've seen this before**).
'a'+'nil'='ANIL'

'for' acts as a link.

(Other definitions for anil that I've seen before include "Colouring" , "Dye for nail" , "Species of blue" , "West Indian shrub, source of indigo" , "Shrub yielding indigo" .)

I've seen this clue in The Telegraph and The Guardian.

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