Jill is a female given name of English origin. It is a diminutive form of the name Julian, which is derived from the Latin name Iulianus, meaning "youthful" or "downy-bearded." The name Jill was originally used as a term of endearment, but it eventually became a common given name in England in the 13th century. It was introduced into the United States by English settlers in the 17th century, and has since become a popular name in English-speaking countries around the world.