Meaning of the Sanskrit Word: vivasvatah

  vivasvataḥ—of the sun-god    Bg 4.4, SB 6.6.40, SB 8.13.1, SB 8.24.11
  vivasvataḥ—of Vivasvān    SB 8.13.8, SB 9.1.2-3

Can't find any compound Sanskrit words containing vivasvatah.