"Iuuen-" is related to Latin "aevum" and Greek "aion" (αἰών) through a common Indo-European root referring to a concept of vital energy or "fertile time". The "iuvenis" is he who has the fullness of vital force. In some inscriptions Jupiter himself is called "Iuuntus", and one of the epithets of Jupiter is "Ioviste", a superlative form of "iuuen-" meaning "the youngest". Iuventas, "Youth", was one of two deities who "refused" to leave the Capitol when the building of the new Temple of Capitoline Jove required the exauguration of deities who already occupied the site.