Cecily is the medieval English form of Cecilia, from the Roman family name Caecilius, which is derived from caecus and means "blind". St. Cecilia, patron saint of music, made the name popular in England in the Middle Ages, and Oscar Wilde used Cecily for the witty young ward in The Importance of Being Earnest. In the US Cecily peaked at number 1061 in 2014 and ranks number 1541 in 2025.