Somehow enrol recluse (5)
I believe the answer is:
loner
'recluse' is the definition.
(lonely or isolated person)
'somehow enrol' is the wordplay.
'somehow' indicates an anagram.
'enrol' with letters rearranged gives 'LONER'.
(Other definitions for loner that I've seen before include "Unsociable person" , "One shunning company" , "One preferring own company" , "Hermit" , "Solitary type" .)