Kaylee is a common name often used for girls. It has various spellings, including Kayley and Kailie, and is derived from the Irish name Caoilinn, meaning "slender" or "fair." The name gained popularity in the United States during the late 20th century and is frequently associated with a cheerful and friendly personality. In popular culture, Kaylee is also known as a character from the television series Firefly, created by Joss Whedon. In the show, Kaylee Frye is the ship's mechanic, known for her technical skills and optimistic attitude. The character has become a beloved figure among fans of the series.