mo·to·cross (mō'tō-krôs', -krŏs') n.
Abbr. MX A cross-country motorcycle race over a closed course of rough terrain with steep hills and sharp curves. Also called scramble.
[French moto-cross : moto, motorcycle (short for motocyclette, from moto-, motor, from moteur, from Latin mōtor, mover; see motor) + English cross(-country).]