Bar limits drunken behaviour of groups? (9)
I believe the answer is:
tribalism
'behaviour of groups?' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'bar limits drunken' is the wordplay.
'drunken' indicates an anagram.
'bar'+'limits'='barlimits'
'barlimits' with letters rearranged gives 'TRIBALISM'.
Can you help me to learn more?
(Other definitions for tribalism that I've seen before include "ethnic customs" , "Strong group loyalty" , "Clannishness" , "clan system" , "divisive tendency" .)