From a classical Greek epithet of the goddess Artemis, referring to her birth on the island of Delos (compare Cynthia). It was taken up by the pastoral poets of the 17th century, and has been moderately popular ever since. It is particularly associated with the cookery writer and broadcaster Delia Smith.
Spanish (García) and Portuguese: from a medieval personal name of uncertain origin. It is normally found in medieval records in the Latin form Garsea, and may well be of pre-Roman origin, perhaps akin to Basque (h)artz ‘bear’.