Английский Этимологический словарь - truckle (n.)

- "small wheel or roller," 1397, from Anglo-Fr. trocle, from L. trochlea "a small wheel, sheaf of a pulley," from Gk. trokhileia "a pulley," from trokhos "wheel," from trekhein "to run." Truckle bed "small bed on wheels that can be stowed under a larger bed" is from 1459.