Deplorable Word

"That was the secret of secrets. It had long been known to the great kings of our race that there was a word which, if spoken with the proper ceremonies, would destroy all living things except the one who spoke it."

- Jadis

The Deplorable Word was an evil incantation from the world Charn, a magical word which, if spoken with the proper ceremonies, would destroy all life except the person who uttered it. This 'ultimate weapon' was used by Queen Jadis, then Empress of Charn, when she lost a civil war with her sister, destroying the population of Charn and turning the planet into a sterile wasteland. The word was highly guarded and the book does not say what it is.

The existence of the Deplorable Word was a closely guarded secret passed down through generations of the magically adept ruling family of Charn, but they had bound themselves with oaths never even to seek knowlege of it. Jadis, more power-hungry than her ancestors, including her recent ones, "searched long for it and paid a terrible price to learn it".

The war with her sister, an extremely bloody world war, was apparently just a power struggle between the two, which the sister won. Jadis waited to use the word until she met with her victorious sister. Then she spoke the Deplorable Word and a moment later she was the only living thing under the sun. Afterward, Jadis showed no remorse, and narcissistically blamed her sister for her act; "Her greed has destroyed the whole world!" Apparently it was used, largely to destroy her sister and her entire army. Besides killing Aslan on the Stone Table, this was Jadis's most evil act known.

While it is not ultimately known why Jadis didn't use the Deplorable Word to destroy Narnia when she was defeated at the Battle of Beruna, before she was killed by Aslan, there is evidence that the spell, along with numerous other magical powers she possessed, may have only worked in the world of Charn: while resisting London police officers during her brief time on Earth, an attempt of hers to kill them with Charnian magic resulted in nothing happening. Alternatively, if the spell would have worked, she may not have had time to use it before she was killed by Aslan, since his attack was a surprise, and the use of the word required certain ceremonies. Or it may be that Aslan had already taken other, unknown actions to prevent her from using it.

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 entry and exit of the palace of Charn.

Aslan warned Digory and Polly that in our own world a secret alike to that of the Deplorable Word might soon be revealed. Given that this took place in the late 1800s, he was likely referring to the atomic bomb.