Mollie is the older spelling of Molly, a medieval pet form of Mary, whose Hebrew source Miryam is usually read as "beloved" or "wished-for child". The -ie ending is the common form in Britain and gives the name a slightly more vintage look. In the United States Mollie ranked number 581 in 2000, its best year in this century, has been outside the top 1000 since 2017 and sits at number 1116 in 2025.