East Slavic name (Russian Перун) which actually means - "lightning"
In Slavic mythology, Perun is the highest God of the pantheon and the God of thunder and lightning. His other attributes were the fire, mountains, the oak, iris, eagle, firmament (in Indo-European languages this was joined with the notion of the sky of stone), horses and carts, weapons (the hammer, axe (Axe of Perun) and arrow) and war. He was first associated with weapons made of stone and later with those of metal.
Like Germanic Thor, Perun is described as a rugged man with a copper beard. He rides in a chariot pulled by a goat buck and carries a mighty axe, or sometimes a hammer. The axe is hurled at evil people and spirits and will always return to his hand.