Meaning of the Sanskrit Word: mahantera

  mahāntera—of the great personalities    Madhya 7.153
  mahāntera—of a great person    Madhya 10.10
  mahāntera—of all the devotees    Madhya 19.132
  mahāntera—of persons who are highly advanced in spiritual life    Antya 3.164

Can't find any compound Sanskrit words containing mahantera.