Meaning of the Sanskrit Word: avirabhut

  avirabhut—appeared    SB 4.30.4, SB 7.4.24, Adi 5.214, Madhya 8.81, Madhya 8.140
  avirabhut—appeared there    SB 8.6.1
  avirabhut—manifested    SB 8.8.8

Can't find any compound Sanskrit words containing avirabhut.