अविकारिन्

a-vikārin

mfn. unchangeable, invariable (as truth) MBh. XII, 5979 andﾠ (superl. -ri-tama) 5986, etc.;

unchangeable (in character), faithful Mn. VII, 190 ;
without change, without being changed Suṡr. ;
not exhibiting any alteration (in one's features) Kathās.