Sociable insect around new diner (8)
I believe the answer is:
friendly
'sociable' is the definition.
(associated in meaning)
'insect around new diner' is the wordplay.
'insect' becomes 'fly' (fly is a kind of insect).
'around' is an insertion indicator.
'new' is an anagram indicator.
'diner' with letters rearranged gives 'riend'.
'fly' enclosing 'riend' is 'FRIENDLY'.
(Other definitions for friendly that I've seen before include "on the same side" , "Amicable and kindly" , "Amiable" , "Well-disposed" , "Affable" .)