While playing with the weak cipher known as ROT13, I decided to check whether any words would ROT13 into other words. I wrote a simple script to cipher a dictionary file, then compared it against itself to look for matches. To my delight, I had found some solid results. Some of the resultant pairs even relate to each other in other ways. I decided this effect was worth naming, and coined 'rotonym' to describe them.
ROT13 is the process of rotating all the letters in a given text by 13 letters, exactly half of the english language alphabet. It is a simple letter substituion cipher which is an example of a Ceasar cipher, originally developed in ancient Rome. ROT13 is its own inverse, that is, when this process is repeated the original text is restored. Below is a list of letters, with their ROT13 counterparts.
'She' likes 'fur'.
The rotonym pair 'gnat tang' is also a Palindrome.
'Terra' is 'Green'.
The rotonym pair 'irk vex' is also a Synonym pair.