Marcella's simply ultimately derived from the god Mars's name.
Names like Marcus, Hermione, Dennis, Aphrodisia, and suchlike were probably originally given in the hopes that, if the child were named after a god/goddess, that deity would grant special divine protection to the child. In a sense, such names could be interpreted as "dedicated to [insert deity]", but the actual meanings of these names have nothing to do with "dedicated".
Miranda "Come... you must eat my child." — From an unknown badfic.
Proud adopter of 15 punctuation marks; see my profile for their names.