Yiit'naii was a rite used within the society of the Taelons and was a sentence used for the most heinous crime amongst their people namely the theft of Core Energy. It involved the accused Taelon's energy being particliesed and dispersed throughout the universe. This act did not kill the Taelon in question as their essence still existed though their form was forever altered. The reasoning for this was because the Taelons believed the destruction of the criminals essence would make their kind just as guilty as the accused.
Zo'or was believed to had been responsible for killing General T'thaan and stealing his Core Energy. This act of cannibalism saw Da'an petition for an energy audit to prove the crime. If shown guilty, Yiit'naii was the sentence though ultimately there were no signs of foreign energy within Zo'or. (Episode: Blood Ties)