A check involving Italian character (5)
I believe the answer is:
aitch
'character' is the definition.
(aitch is a kind of character)
'a check involving italian' is the wordplay.
'check' becomes 'ch' (I've seen this in other clues).
'involving' indicates putting letters inside.
'italian' becomes 'it'.
'a'+'ch'='ach'
'ach' enclosing 'it' is 'AITCH'.
(Other definitions for aitch that I've seen before include "that I will immediately succeed" , "the start of hives?" , "8th letter of the alphabet" , "bone" , "first bit of hymn?" .)