Ibn Khaldun's term for group solidarity or social cohesion, strongest in kinship groups living in harsh conditions, which enables a group to seize and found a state and whose erosion explains dynastic decline.
In more detail
In the Muqaddimah (1377) Ibn Khaldun argued that cohesive groups from the desert or countryside conquer weakened urban dynasties; once in power, rulers monopolise authority, adopt luxury and rely on clients and mercenaries, so cohesion fades and a new group replaces them. Religion can strengthen 'asabiyya by uniting rival groups. The concept has been taken up by historical sociologists and by Peter Turchin's mathematical models of state rise and fall; critics caution against applying a model drawn from medieval North Africa to modern bureaucratic states.