The name is from the French word for the lilac flower. It first came into use in France in the 18th-Century, being introduced as a recommended name in the calendrier républicain (repulican calendar). The republican calendar was a product of the French Revolution, in which Catholic saints’ names were replaced with names that came directly from French words, mostly denoting nature and abstract concepts.
The name fell out of use shortly after that and came back in sporadic use in the 1900s. In recent years, due to the trend of other rediscovered Revolutionary Names, such as Garance & Capucine, it has returned to the French charts. Lilas is currently the 358th Most Popular Female Name in France.
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