Defensor, the Latin word from which Defender and its equivalents in various languages stem, refers to:

• Defensor civitatis, a function in the Roman and Byzantine Empire, with later imitations
• In canon law: defensor matrimonii
• The princely title Fidei defensor, Defensor Perpétuo do Império do Brasil
• The title of various publications, such as the tract Defensor pacis
• A surname, as in Miriam Defensor-Santiago
• A Marvel Comics superhero that debuted in the original Contest of Champions
• Any of several characters from the Transformers. Defensor (Transformers)
• Defensor Sporting Club, football club in Uruguay

The plural Defensores can be:

• The name of various sports teams, especially in Latin America