TORTOISE, noun tor'tis.] from Latin tortus, twisted.] 1. An animal of the genus Testudo, covered with a shell or crust. 2. In the military art, a defense used by the ancients, formed by the troops arranging themselves in close order and placing their bucklers over their heads, making a cover resembling a tortoise-shell.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI