(French) form of Christina. It was popular in the medieval period, when it appears to have been used interchangeably with Christian, and again in Britain at the end of the 19th century. In the United States it was particularly popular from the 1950s to the 1970s.
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’.