"Communitas as a social form alternates with "normal" social structure, and is, according to Victor Turner's theories, not limited to the liminal phase in rites de passage. [...] [Many social] phenomena are difficult to place within van Gennep's rites de passage model of separation, liminality and reintegration, [but] may more naturally be considered a form of "anti-structure", alternating with normal social structure. Turner detached the phenomena liminality and communitas from the model for transitional rituals (Turner 1969). The two social models exist simultaneously in a society, and no normal society can function adequately without this dialectic with communitas (Turner 1967:129). The alternation between the two states follows successively and is enforced naturally."
(Definition quoted from: Eggen, Øyvind: Troens Bekjennere: Kontinuitet og endring i en læstadiansk menighet, translated by Finn Sivert Nielsen.)