A defender; one who defends (archaic or legal term, particularly in historical contexts).
From Latin defensor, from defendere 'to defend.' This term appears in Roman law and medieval charters, particularly defensor civitatis (defender of the city) and was used in ecclesiastical contexts.
In medieval times, a defensor civitatis was an official appointed to protect the poor from corruption—the original ombudsman. The role was so important it's literally written into the structure of old cities.
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