n. (context military historical English) An early, very small, lightly armoured tank, with a crew of one or two, equipped with machine guns.
A tankette is a tracked armoured fighting vehicle that resembles a small tank, roughly the size of a car. It is mainly intended for light infantry support and scouting. Colloquially it may also simply mean a small tank.
Several countries built tankettes between the 1920s and 1940s, and some saw limited combat in the early phases of World War II. The vulnerability of their light armor, however, eventually led armies to abandon the concept.