The lad Tuohy upset (5)

I believe the answer is:

youth

'the lad' is the definition.
(thesaurus)

'tuohy upset' is the wordplay.
'upset' indicates anagramming the letters.
'tuohy' is an anagram of 'YOUTH'.

(Other definitions for youth that I've seen before include "Adolescent" , "period before getting old" , "Inexperience" , "Early days" , "Early part of life" .)

I've seen this clue in The Times.

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