The Quadricycle was an early form of automobile. Earliest models were propelled by a small steam engine, then designers switched to early internal combustion engines as they became available. The word is derived from the fact that it had four wheels and used technology derived from the bicycles of the era.

• 1884 De Dion Bouton "La Marquise" Quadricycle (Steam runabout)
• 1884 De Dion Bouton Victoria Quadricycle
• 1889 Daimler Quadricycle
• 1901 Peugeot Type 2, a direct descendant of the Daimler Quadricycle, and the first automobile of the Peugeot company
• Peugeot Type 3 Quadricycle
• Le Rudge Quadricycle Tandem
• 1896 Ford Quadricycle, Henry Ford's first automobile design
• 1899 Orient Quadricycle (aka Orient Autogo)
• 1900 De Dion Bouton Quadricycle
• 1901 Truffault Quadricycle

Additional motorized four-wheelers:

• Duryea Motor Wagon
• Benz Velo

Quadricycle, quadracycle, quadcycle, quadrocycle and quad all refer to vehicles with four wheels. More specifically these terms may refer to:

• All-terrain vehicle, also known as quad or quad bike
• Motorized quadcycle, a motorcycle with four wheels
• Automobile, the first experimental steam automobiles were termed steam quadricycles
• Low-speed vehicle, referred to in some countries as a quadricycle
• Quadricycle, European classifications for light four-wheeled motorized vehicles: light quadricycles, category L6e, and (heavy) quadricycles, category L7e

• Quadracycle, a four-wheeled style of cycle
• Velomobile, an enclosed human-powered vehicle