köken: Inherited from Middle French chascun, from Old French chascun, from Vulgar Latin *cascunum, *casquunum, a conflation of quisque unum (“each one”) + *cata unum, a variant form showing a derivative of Ancient Greek κατά (katá) (this variant form survived into Old French as chaün). Compare Occitan cadun, chascun, Catalan cadascun, Italian ciascuno.
aile: à chacun son goût, chacun pour soi, tout un chacun