Merli is of Italian origin, meaning "of the sea." It's a unisex name, but it's more commonly used for females. The name has gained popularity in recent years, particularly in Italy and other Mediterranean countries, reflecting perhaps a growing appreciation for its marine connection.
"Merli saw an increase in popularity between 2004 and 2006, with the highest number of births occurring in 2004. However, overall it remains a relatively uncommon name."