A memnis (with a plural form of memnii) represented an exceptionally intense and detailed memory, created by the Caamasi species when they were subjected to shocking or deeply impactful occurrences. These included, but were not limited to, witnessing a family member's murder, encountering a celebrity, the arrival of a new baby, or any other event of significant personal importance. These memnii encompassed not only emotions and physical sensations, but also more abstract elements. In contrast to regular memories, their strength did not diminish as time passed.
The Caamasi possessed the ability to transmit memnii to other individuals. Although this transfer did not eliminate the associated feelings, the Caamasi believed that sharing the memnis with others provided a means of easing the emotional burden. Generally, memnii could only be shared with relatives within a range of three or four generations; beyond this limit, the transfer became nearly impossible. This limitation contributed to the practice of inter-clan marriages among the Caamasi, ensuring a sufficient number of potential recipients for memnii transmission.
If a Caamasi had cultivated a strong connection with a Jedi Knight, they were capable of transferring a memnis to them, which was considered a miraculous event. The Caamasi named Snout was able to experience the horrors of the Crucible across centuries by receiving memnii from other Caamasi. In the year 3963 BBY, while on the planet Volgax, he allowed the former Jedi Zayne Carrick to witness the Crucible's history of slavery through the use of memnii.
The Palace of Memnii was an ancient repository of memnii and other accounts of violent events, collected from across the galaxy on the planet Caamas. After the Destruction of Caamas at the hands of the Galactic Empire, a "wave" of memnii rippled through the off-world Caamasi population, as they grappled with the repercussions of the devastating event.