夷俗[izoku] customs of the barbarians
雅俗[gazoku] refined and vulgar
還俗[genzoku] return to secular life
旧俗[kyuuzoku] old customs
古俗[kozoku] old custom

州俗[shuuzoku] local customs
淳風美俗[junpuubizoku] good morals and manners
世俗[sezoku] common customs
世俗化[sezokuka] secularization
世俗主義[sezokushugi] secularism

ヨガの流行[yoganoryuukou] the cult of yoga
亜流[aryuu] bad second
暗流[anryuu] undercurrent
一次電流[ichijidenryuu] primary current
一流[ichiryuu] first-class

溢流[itsuryuu] overflow
渦流[karyuu] swirling current
押流す[oshinagasu] to wash away
横流し[yokonagashi] diversion into illegal channels
横流れ[yokonagare] flowing into the black market