Vidasus was an Illyrian god of forests and vegetation, the divine partner of the goddess Thana. He is attested in Roman-period epigraphy, most fully at the warm springs of Topusko in Pannonia Superior (modern Croatia), where votive monuments name him and Thana together as an inseparable couple and where the Romans recognised the pair as their own Silvanus and Diana. As a woodland and pastoral deity, patron of the wild and of herdsmen, he belonged to the same religious world as the widely worshipped Dalmatian Silvanus, an autochthonous god of the Delmatae usually shown flanked by female woodland companions. His name is most often derived from the Indo-European root *widhu- 'tree, forest', the same element that appears in the name of the Old Norse god Víðarr, who dwells amid grass and brushwood.