Testudo (which meant "tortoise" in classical Latin) may refer to:

• Battering ram, an armored siege engine with metal plating on the top to protect from missiles fired from above
• Chevrolet Testudo, a concept car designed and built by Bertone on a Chevrolet Corvair unibody chassis
• Steel Testudo or the Nationalist-Socialist Party of Romania, 1930s political party
• Testudo (mascot), the mascot of University of Maryland, College Park
• Testudo (genus), a genus in the tortoise family of turtles
• Testudo formation, a Roman military tactic which involved a formation of soldiers using their shields to form a tortoise-shell-like protective cover against enemy weapons
• Testudo, the Latin variant of the Greek chelys harp, involving a sound-box made from a tortoise shell
• Testudo, an obsolete constellation now in the constellation of Pisces

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