Loyalty, say, found in association (10)
I believe the answer is:
allegiance
'loyalty' is the definition.
(allegiance is a kind of loyalty)
'say found in association' is the wordplay.
'say' becomes 'eg' (both can mean 'for example').
'found in' is an insertion indicator.
'association' becomes 'alliance' (I've seen this before).
'eg' going into 'alliance' is 'ALLEGIANCE'.
(Other definitions for allegiance that I've seen before include "Loyalty to a group or cause" , "commitment to a cause" , "Loyalty (to a superior)" , "duty" , "Fidelity" .)