quad bike

Meanings

1. A small off-road four-wheeled powered vehicle, especially of a design derived from a motorcycle, usually used for recreation or farm work.

Etymology

From quad (“four (“4”)”) + bike (“bicycle”). From being a 4-wheeled quadricycle vehicle that is ridden astride like a dirt bike (“motorcycle”). The oxymoronic character of the term, via the etymonic-level contradiction of quad ("four") in juxtaposition with the bi- behind bike ("two"), is simply ignored by idiom, as such contradictions often are.