moped
Motor vehicles
mo·ped /ˈməʊped $ ˈmoʊ-/ noun [countableC] 
TTCa small two-wheeled vehicle with an engine 机动自行车，助动车 → motorcycleExamples from the Corpus
moped• So far this year, 29,060 mopeds have found buyers-up 35 per cent on the same period in 1999.• They moved 3232 mopeds compared with 2739 in November 1999.• And 3578 mopeds were sold last month against October 1999's 2719.• That means bike sales are up 2.6 per cent and mopeds up 34.2 per cent.• Fiats and mopeds clog the streets of Palermo, Ragusa, and the smaller cities.• There was hardly any traffic, just a few parked cars and a cluster of mopeds around the door of the bar opposite.• While walking the rest of the way, you are run over by kids on mopeds.
(1900-2000) Swedish motor “motor” + pedal “pedal”