The meaning of the name Mylie is Smiley. The origin of the name Mylie is American. This is the culture in which the name originated, or in the case of a word, the language.
The name Miley grew in popularity after the success of teen actress and singer, Miley Cyrus. Although Miley's birth name was Destiny Hope, she was nicknamed "Smiley Miley" by her parents as a baby. Cyrus legally changed her name to Miley in 2008.