noun: Initialism of motor torpedo boat. [(military, nautical) A torpedo boat powered by an internal combustion engine rather than a steam engine.]
noun: Initialism of mountain bike. [A bicycle specially designed for off-road riding, typically with straight, flat handlebars, a heavier frame than road bikes, higher ground clearance, and wider tires, sometimes with knobs on them for greater traction.]
noun: Initialism of mountain biking. [(sports) off-road cycling using a mountain bike]
