Colleen comes from the Irish word cailín, which simply means "girl" or "young woman". Oddly, it is hardly used as a name in Ireland itself; it became popular among Irish Americans and Australians in the 20th century and belongs to the actress Colleen Dewhurst. Colleen ranked 455 among US girls in 2000, peaked at number 439 in 2001, left the top 1000 in the following decade and stands at number 2829 in 2025.