Duet Lois performed in isolation (8)
I believe the answer is:
solitude
'isolation' is the definition.
(I know that solitude is a type of isolation)
'duet lois performed' is the wordplay.
'performed' is an anagram indicator.
'duet'+'lois'='duetlois'
'duetlois' is an anagram of 'SOLITUDE'.
'in' is the link.
(Other definitions for solitude that I've seen before include "Privacy" , "Being by oneself" , "Lone state" , "Lone condition" , "Absence of company" .)