UK peer adjusted wig (6)
I believe the answer is:
peruke
'wig' is the definition.
(peruke is a kind of wig)
'uk peer adjusted' is the wordplay.
'adjusted' is an anagram indicator.
'uk'+'peer'='ukpeer'
'ukpeer' is an anagram of 'PERUKE'.
(Other definitions for peruke that I've seen before include "Old fashionable wig" , "18th-century wig" , "Ancient wig" , "Periwig" .)