prstham

pṛṣṭham — back; SB 2.1.32
tri-pṛṣṭham — the topmost planetary space; SB 2.7.40
aśma-pṛṣṭham — having a surface of stone; SB 5.26.28
nāka-pṛṣṭham — the heavenly planets or Dhruvaloka; SB 6.11.25
nāka-pṛṣṭham — in the heavenly kingdom; SB 8.17.15
nāka-pṛṣṭham — heaven; SB 10.16.37
nāka-pṛṣṭham — the roof of heaven; SB 10.89.43-44
tri-pṛṣṭham — the topmost planet (Satyaloka); CC Madhya 24.21