Jilian is of American origin, derived from the French girl's name Julie. It means 'youthful' or 'downy young'. The name Jilian gained popularity during the late 20th century and has been consistently used since then. It has a soft, feminine sound with its repetition of the letter 'l', making it appealing to many.
"Jilian peaked in popularity during the late '80s to early '90s with a high of 44 births in 1982 and an average of around 30 births per year from 1987 to 1991. However, its usage significantly declined throughout the 2000s, reaching as low as 5 births in both 2011 and 2013."