Back-formation

Back-formation is when people take a longer word and make a shorter word out of it by removing part of the longer word that they think doesn't belong. It's like making a new word by un-doing an old word.

For example, the word "burgle" was made by taking the word "burglar" and removing the "ar" at the end. It's like taking away a part of a toy that you don't need anymore and making a new toy with it.

People do this to make language simpler and easier to use. But sometimes new words made by back-formation don't catch on and people just keep using the longer word.