And Mercedes IS a girl's name. I believe Herr Benz (or was it Herr Daimler) named the car after his business partner's daughter
Mercédès Adrienne Ramona Manuela Jellinek (September 16, 1889 – February 23, 1929) was the daughter of Austrian automobile entrepreneur Emil Jellinek and his wife Rachel Goggmann Cenrobert. She was born in Vienna.[1] She is best known for her father having Daimler-Motoren-Gesellschaft's line of Mercedes cars named after her, beginning with the Mercedes 35 hp model of 1901.