[ ˌlʌmpənprəʊlɪ'tɛ:rɪət ]
■ noun [treated as sing. or plural ] (especially in Marxist terminology) the apolitical lower orders of society uninterested in revolutionary advancement.
Origin
1920s: from Ger. (orig. used by Karl Marx), from Lumpen 'rag, rogue' + proletariat .