 in the science fiction babylon 5 saga, a shon'kar (or shankar) is a narn blood oath. the blood oath is taken by individual narn against those who had wronged the individual narn or their family. an individual narn is expected to not rest until the target of the shon'kar has been killed. if a narn fails to carry out a shon'kar, the other members of his or her family are expected to carry out the shon'kar. in the episode "deathwalker", na'toth nearly kills the dilgar war leader jha'dur. na'toth's family had sworn a blood oath against jha'dur for what she had done to na'toth's grandfather. while na'toth was unable to kill jha'dur, the vorlons take care of the matter when they destroy jha'dur's ship in order to keep her knowledge of immortality from being revealed to the younger species of the galaxy. later, in the episode sic transit vir, a narn angrily confronts vir and lyndisty, who was to be his wife. captain sheridan keeps the narn from killing vir. the narn is stopped by security, and is shot when he tries to kill vir. right before being shot, the narn yells "shon'kar." at first the oath is assumed to be against vir, but it's actually against lyndisty for her role in helping to kill narn villagers.  
Babylon_5