Leonardo da Vinci designed a covered armored vehicle that is commonly called a tank.
His fighting vehicle, drawn around 1487–1489, had a conical shell inspired partly by a tortoise’s protective form. It was intended to carry several men and fire weapons through openings around its perimeter. The vehicle would have been moved by cranks connected to wheels inside the armored body.
Leonardo’s design was not a modern tank: it had no engine, turret, or tracked propulsion, and it was never built for Renaissance warfare. A famous drawing also appears to contain a gearing error that would prevent the vehicle from moving as shown. Some historians think the error may have been deliberate, perhaps to keep the design from being copied, although that explanation is not certain.
The modern word “tank” belongs to twentieth-century armored warfare. Leonardo’s machine is called a tank because its enclosed armored shape and battlefield role resemble later armored fighting vehicles.