... the present holder’s fabulous repartee! (4,4)
I believe the answer is:
'the present holder's' is the definition.
(as in 'a partridge in a pear tree')
'fabulous repartee' is the wordplay.
'fabulous' is an anagram indicator.
'repartee' anagrammed gives 'PEAR-TREE'.
(Other definitions for pear tree that I've seen before include "it should bear fruit" , "Conference provider" , "Partridge roost at Christmas?" , "present setting" , "What comes with start of Christmas" .)