What does "testudo" mean?

Testudo: (Rom. Antiq.) A cover or screen which a body of troops formed with their shields or targets, by holding them over their heads when standing close to each other. This cover resembled the back of a tortoise, and served to shelter the men from darts, stones, and other missiles. A similar defense was sometimes formed of boards, and moved on wheels.

Additional senses

  1. 2.(Mus.) A kind of musical instrument. a species of lyre; -- so called in allusion to the lyre of Mercury, fabled to have been made of the shell of a tortoise.

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