Many a hoodie conceals lout (5)
I believe the answer is:
yahoo
'lout' is the definition.
(I've seen this before)
'many a hoodie conceals' is the wordplay.
'conceals' indicates the answer is hidden within the clue.
'YAHOO' can be found hidden inside 'many a hoodie'.
(Other definitions for yahoo that I've seen before include "Coarse type" , "Brutish lout" , "Uncouth person" , "Brutal lout" , "Exclamation of joy; brute" .)