The Section 320 in India defines grievous hurt. The punishment is enhanced when the hurt is grievous.
Section 320 in the Indian Penal Code Wikipedia
The following kinds of hurt only are designated as "Grievous":First
Permanent privation of the sight of either eyeThird
Permanent privation of the hearing of either earFourth
Privation of any member or jointFifth
Destruction or permanent impairing of the powers of any member or joint,Sixth
Permanent disfiguration of the head or faceSeventh
Fracture or dislocation of a bone or tooth,Eighth
Any hurt which endangers life or which causes the sufferer to be during the space of twenty days in severe bodily pain, or unable to follow his ordinary pursuits.