The city of Merida, Mexico was named after the Spanish city Merida. The original name of this town in Spain was "Emerita Augusta" and was then shortened to Merida. So, Merida is a shortened version of Emerita. This is a Latin name meaning "a woman who has achieved a place of honor." Since Merida is a derivative I would say that it would carry the same meaning in much the same way that Sally and Sadie have the same meaning as Sarah.