From Proto-Italic *jokos, from Proto-Indo-European *yek- (“to speak”). Compare Old High German jehan, Welsh iaith, Breton yezh. Possibly cognate with English Yule, Danish Jule, Norwegian Bokmål Jul, Swedish Jul, and Norwegian Nynorsk jol.
Ćwicz mówienie i zapamiętywanie " iocus " i wielu innych słów i zdań z łaciński .