Complaint in frail men treated (7)

I believe the answer is:

ailment

'complaint' is the definition.
(I know that complaint can be written as ailment)

'in frail men treated' is the wordplay.
'in' indicates the answer is hidden within the clue.
'AILMENT' is hidden within 'frail men treated'.

(Other definitions for ailment that I've seen before include "Physical disorder" , "Tummy upset, for instance" , "Complaint, affliction" , "problem" , "Minor illness" .)

I've seen this clue in The Telegraph.

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