Crossword Genius

Harmful nuisance I supplied money to for a while (9)

Ross

I believe the answer is:

pestilent

'harmful' is the definition.
('pestilent' can be similar in meaning to 'harmful')

'nuisance i supplied money to for a while' is the wordplay.
'nuisance' becomes 'pest' (I've seen this before).
'supplied money to for a while' becomes 'lent'.
'pest'+'i'+'lent'='PESTILENT'

(Other definitions for pestilent that I've seen before include "Pernicious" , "Vexatious" , "Plaguey" , "Peel tints (anag) - extremely tiresome" , "Annoying" .)

I've seen this clue in The Guardian.
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