riffraff

詳細解釋：

riff.raff

n.（名詞）
People regarded as disreputable or worthless.
烏合之眾，下等人，流氓：被認為聲名狼藉的或不足道的人
Rubbish; trash.
垃圾，廢物

來源：
Middle English riffe raffe
中古英文 riffe raffe
from rif and raf [one and all]
源自 rif and raf [個個都，全都]
from Anglo-Norman rif et raf, rifle et rafle
源自 英法文 rif et raf, rifle et rafle
Old French rifler [to rifle] * see rifle 2
古法文 rifler [劫掠] *參見 rifle2
Old French raffler [to carry off] from raffle [act of seizing] * see raffle
古法文 raffler [搶走] 源自 raffle [搶劫的動作] *參見 raffle