What is the general technical meaning of rukhsah?

Prescribed Acts and Prohibitions: Fard, Wajib, Sunnah, Nafl, Haram, Makruh, Azimah and Rukhsah

• Permanently converting every fard into nafl
• Moving a matter from hardship to ease under justified conditions
• Licensing all forbidden acts without evidence
• Another name for rejecting sunnah