Exhibitionist who's tailored hat (10)

I believe the answer is:

showboater

'exhibitionist' is the definition.
(someone who shows off)

'who's tailored hat' is the wordplay.
'tailored' indicates anagramming the letters (the letters are customised ).
'hat' becomes 'boater' (boater is a kind of hat).
'whos' is an anagram of 'show'.
'show'+'boater'='SHOWBOATER'

(Another definition for showboater that I've seen is " Exhibitionist".)

I've seen this clue in The Telegraph.

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