A fool disposed to be distant (5)
I believe the answer is:
aloof
'be distant' is the definition.
(synonyms)
'a fool disposed' is the wordplay.
'disposed' indicates anagramming the letters.
'fool' is an anagram of 'loof'.
'a'+'loof'='ALOOF'
'to' acts as a link.
(Other definitions for aloof that I've seen before include "Cool, distant" , "Coldly distant" , "rather cold" , "Unfriendly or distant like a fool" , "Withdrawn, distant" .)