The Deplorable Word was a spell from the now-dead World of Charn. If spoken with the proper ceremonies, this word would destroy all living things in the world, except for the person who spoke it. This 'ultimate weapon' was used by Jadis, the last Queen of Charn, when she lost a civil war against her sister. Her action destroyed the remaining population of Charn and turned the world into a sterile wasteland.
The existence of the Deplorable Word was a closely guarded secret, passed down through generations of the ruling family of Charn, and who had bound themselves with oaths to never even seek knowledge of it. Jadis, however, was far more power-hungry than her ancestors, and she "learned it in a secret place and paid a terrible price to learn it".
The war against her sister - an extremely bloody conflict and apparently just a power struggle between the two - ended in Jadis' defeat. Jadis waited to use the word until she met with her victorious sister on the steps to the royal palace, offering her the chance to surrender if she acknowledged Jadis as Charn's one true ruler. Her sister, however, refused, and so Jadis spoke the Deplorable Word; a moment later she was the only living thing left under her world's dying red sun.
Recounting her story later to Polly Plummer and Digory Kirke, Jadis showed no remorse, and even narcissistically blamed her sister for her own act, declaring "Her greed has destroyed the whole world!"
- It should be noted that when Polly and Diggory first arrived in Charn, there were no remains of people, animals or even plants, except for some type of dead climbing plant that had wound around a pillar. Since the Deplorable Word only affects living things, this implies that the vines were already dead before Jadis spoke the word.
- Aslan later warned Digory and Polly that in our own world, a secret similar to that of the Deplorable Word might soon be revealed. Given that the story took place around the year 1900, He may have been referring to the atomic bomb.
- Interestingly, Jadis never attempted to use the Deplorable Word to destroy Narnia, from the moment of that world's creation until she was killed by Aslan following her defeat at the Battle of Beruna. There is evidence, however, that the numerous magical powers she once possessed may have only worked in the World of Charn; during her brief time on Earth, her attempt to attack Letitia Ketterley with magic produced no result at all.
- The Deplorable Word should not be confused with a lesser spell, also involving a magic word, which Jadis used to destroy the gates of the palace of Charn.
- MN V
- MN IV