Funny aunt about to show character (6)
I believe the answer is:
nature
'character' is the definition.
(thesaurus)
'funny aunt about' is the wordplay.
'funny' indicates an anagram.
'about' becomes 're' (regarding).
'aunt' anagrammed gives 'natu'.
'natu'+'re'='NATURE'
'to show' is the link.
(Other definitions for nature that I've seen before include "variety" , "Fundamental character" , "Disposition; temper" , "mother, so-called" , "Essential quality" .)