Crossword Genius

As in a leg a curious absence of pain (9)

Ross

I believe the answer is:

analgesia

'absence of pain' is the definition.
(I've seen this before)

'as in a leg a curious' is the wordplay.
'curious' indicates anagramming the letters.
'as'+'in'+'a'+'leg'+'a'='asinalega'
'asinalega' with letters rearranged gives 'ANALGESIA'.

(Other definitions for analgesia that I've seen before include "The relief of pain by drugs" , "Inability to feel pain" , "Loss of pain" , "No hard feelings" , "painless" .)

I've seen this clue in The Sun and The Times.
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