- wheel
-
—wheelless, adj./hweel, weel/, n.1. a circular frame or disk arranged to revolve on an axis, as on or in vehicles or machinery.2. any machine, apparatus, instrument, etc., shaped like this or having a circular frame, disk, or revolving drum as an essential feature: a potter's wheel; roulette wheel; spinning wheel.4. Naut.a. a circular frame with an axle connecting to the rudder of a ship, for steering: He took the wheel during the storm.b. a paddle wheel.c. a propeller.5. Informal. a bicycle.6. a round object, decoration, etc.: a wheel of cheese; a design of red wheels and blue squares.7. an old instrument of torture in the form of a circular frame on which the victim was stretched until disjointed.8. a circular firework that revolves rapidly while burning; pinwheel.9. a rotating instrument that Fortune is represented as turning in order to bring about changes or reverses in human affairs.10. wheels,a. moving, propelling, or animating agencies: the wheels of commerce; the wheels of thought.b. Slang. a personal means of transportation, esp. a car.11. a cycle, recurring action, or steady progression: the wheel of days and nights.12. a wheeling or circular movement: the intricate wheels of the folk dances.14. Informal. someone active and influential, as in business, politics, etc.; an important person: a big wheel.15. at the wheel,a. at the helm of a ship, the steering wheel of a motor vehicle, etc.b. in command or control: Her ambition is to be at the wheel of a large corporation by the age of 40.17. spin one's wheels, Informal. to expend or waste effort to no avail: He spun his wheels on that project for two years.18. wheels within wheels, an involved interaction of motives or agencies operating to produce the final result: Government agencies are a study of wheels within wheels.v.t.19. to cause to turn, rotate, or revolve, as on an axis.20. to perform (a movement) in a circular or curving direction.21. to move, roll, or convey on wheels, casters, etc.: The servants wheel the tables out.v.i.23. to turn on or as on an axis or about a center; revolve, rotate, or pivot.24. to move in a circular or curving course: pigeons wheeling above.25. to turn so as to face in a different direction (often fol. by about or around): He wheeled about and faced his opponent squarely.26. to change one's opinion or procedure (often fol. by about or around): He wheeled around and argued for the opposition.27. to roll along on or as on wheels; travel along smoothly: The car wheeled along the highway.28. Brit. Mil. to turn: Right wheel![bef. 900; (n.) ME whel(e), OE hweol, hweohl; c. D wiel, ON hjol; akin to Gk kýklos (see CYCLE); (v.) ME, deriv. of the n.]
* * *
ICircular frame of hard material capable of turning on an axle.Wheels may be solid, partly solid, or spoked. The oldest known wheel was a wooden disk of planks held together by crosspieces. A pottery wheel or turntable was developed с 3500 BC in Mesopotamia. The spoked wheel appeared с 2000 BC on chariots in Asia Minor. Later developments included iron hubs that turned on greased axles. Perhaps the most important invention in human history, the wheel was essential to developing civilizations, and has remained essential to power generation, transportation, industrial manufacturing, and countless other applications.II(as used in expressions)* * *
a circular frame of hard material that may be solid, partly solid, or spoked and that is capable of turning on an axle.A Sumerian (Sumer) (Erech) pictograph, dated about 3500 BC, shows a sledge equipped with wheels. The idea of wheeled transportation may have come from the use of logs for rollers, but the oldest known wheels were wooden disks consisting of three carved planks clamped together by transverse struts.Spoked wheels appeared about 2000 BC, when they were in use on chariots in Asia Minor. Later developments included iron hubs (centerpieces) turning on greased axles, and the introduction of a tire in the form of an iron ring that was expanded by heat and dropped over the rim and that on cooling shrank and drew the members tightly together.The early waterwheels (waterwheel), used for lifting water from a lower to a higher level for irrigation, consisted of a number of pots tied to the rim of a wheel that was caused to rotate about a horizontal axis by running water or by a treadmill. The lower pots were submerged and filled in the running stream; when they reached their highest position, they poured their contents into a trough that carried the water to the fields.The three power sources used in the Middle Ages—animal, water, and wind—were all exploited by means of wheels. One method of driving millstones for grinding grain was to fit a long horizontal arm to the vertical shaft connected to the stone and pull or push it with a horse or other beast of burden. Waterwheels and windmills were also used to drive millstones.Because the wheel made controlled rotary motion possible, it was of decisive importance in machine design. Rotating machines for performing repetitive operations driven by steam engines were important elements in the Industrial Revolution. Rotary motion permits a continuity in magnitude and direction that is impossible with linear motion, which in a machine always involves reversals and changes in magnitude.* * *
Universalium. 2010.