More info about the name "Felicitas"
Felicitas is a Latin variant of Felicity. Felicity originates in Latin language and means "filled with happiness". Felicity was the name of a 2nd century Christian saint. As a feminine given name it has been fairly popular in the United States, but gained even more popularity in the United Kingdom. It was popularized by the name of a 1998 TV show and also the name of the main character, Felicity.