testudo

TESTU'DO, n. [L.] A tortoise. Among the Romans, 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.

1. In medicine, a broad soft tumor between the skull and the skin, called also talpa or mole, as resembling the subterraneous windings of the tortoise or mole.