Fabian Prewett (d. 1981) was a pure-blood wizard, the brother of both Gideon and Molly. Fabian was a member of the Order of the Phoenix during the First Wizarding War. He was murdered by five Death Eaters before the end of the war, along with his brother.
Fabian is the English form of the Latin Fabianus, which was the name given to emancipated slaves in Rome. It is derived from Fabius, the name of a very influential Roman patrician family, whose members included many politicians and soldiers. The most notable of the Fabian family was Quintus Fabius Maximus Verrucosus, who was given the epithet Cunctator, "the Delayer", because of the unorthodox strategies he employed in the Second Punic War against Hannibal. He developed the Fabian strategy of warfare.