Meaning of the Sanskrit Word: tapase

  tapase—for the matter of penance    SB 3.12.20
  tapase—to execute austerities    SB 7.7.2
  tapase—for executing austerity    SB 4.24.14
  tapase—for practicing austerities    SB 8.1.7
  tapase—severe penances    SB 2.7.8
  tapase—for undergoing austerities    SB 4.29.81

Can't find any compound Sanskrit words containing tapase.