Left guy out, having registered illness (5)

I believe the answer is:

lurgy

'illness' is the definition.
(I've seen this before)

'left guy out having registered' is the wordplay.
'left' becomes 'l' (common abbreviation).
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'having' is an insertion indicator.
'registered' becomes 'R' (abbreviation, as in registered trademark).
'guy' with letters rearranged gives 'ugy'.
'ugy' enclosing 'r' is 'urgy'.
'l'+'urgy'='LURGY'

(Another definition for lurgy that I've seen is " Illness".)

I've seen this clue in The Daily Express.

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