tricycle
Word family nountricyclertricyclingtricyclisttricycleadjectivetricyclic
Bicycles, carts, horses
tri·cy·cle /ˈtraɪsɪkəl/ noun [countableC] 
TTBa bicycle with three wheels, especially for young children 〔尤指幼儿骑的〕三轮自行车Examples from the Corpus
tricycle• As he opened the door and looked out he thought he heard the squeak of a tricycle.• It seemed to withstand the onslaught of bicycles, tricycles and roller skates with scarcely a scratch to show.• Both little girls were silent, pale and tight-lipped while Liz tended to the gash, caused by a falling tricycle.• I pushed Janir home on his tricycle, made him dinner and put him to bed.• There are no tricycles in the hallway, no small sandals behind the doors.• One young boy exercised by riding a red tricycle around the wards.• They came to steal a Big Wheel tricycle.• And there's a special appearance from the Dean of Hereford cathedral, complete with tricycle.
(1900-2000) French tri- + Greek kyklos “circle, wheel”