Meaning of the Sanskrit Word: mamanthuh

  mamanthuḥ—churned    SB 4.13.19-20, SB 4.14.43, SB 8.7.5, SB 8.7.13, SB 9.13.12
  mamanthuḥ—again began to churn    SB 8.8.1

Can't find any compound Sanskrit words containing mamanthuh.