wheel(redirected from pregnancy wheel)
Also found in: Dictionary, Thesaurus, Medical, Legal.
wheel.Through the many millennia of the Paleolithic period and the Neolithic period no use of the wheel was known to humans. Its use was not known to the Native Americans until the Europeans introduced it. In the Old World it came into use in the Bronze Age, when oxen and horses were first used as draft animals and wheeled vehicles were devised. Wheels for vehicles were at first solid wooden disks; spoked wheels were introduced c.2700 B.C. The potter's wheel was invented in the Bronze Age, earlier pottery being made, like that of the Native Americans, without the use of the wheel. See geargear,
toothed wheel, cylinder, or cone that transmits motion from one part of a machine to another; it is one of the oldest means of transmitting motion. When the teeth of two gears are meshed, turning one gear will cause the other to rotate.
..... Click the link for more information. ; tiretire,
device made of rubber and fabric and attached to the outer rim of a vehicle wheel. Solid rubber tires were in limited use before 1850; they are still used in some special applications, e.g., for industrial trucks in factories.
..... Click the link for more information. ; wheel and axlewheel and axle,
simple machine consisting of a wheel mounted rigidly upon an axle or drum of smaller diameter, the wheel and the axle having the same axis. It is fundamentally a form of lever, the center common to both the wheel and the axle corresponding to the fulcrum, the
..... Click the link for more information. .
See R. J. Forbes, Studies in Ancient Technology (1955); E. Tunis, Wheels (1955); W. Owen et al., ed., Wheels (1972).
a part found in machines and mechanisms; it takes the form of a round plate or of a rim joined by spokes to a hub. A wheel can spin freely on an axle or be fastened to it, and it is used to transmit or convert rotary motion.
The wheel, one of the greatest inventions of mankind, has been known since about the middle of the fourth millenium B.C. (in Mesopotamia). The wheel was an improvement on the wooden rollers that had been used for millennia to move loads. Initially the wheel was a round plate fitted to an axle. In the second millennium B.C., its design was improved: the wheel with spokes, a hub, and a circular rim appeared. Later a metal rim came into use for increased strength and durability, and much later the rim was replaced by the tires used in motor vehicles.
The invention of the wheel furthered the development and improvement of crafts and trades: the potter’s wheel, the grinding wheel in mills, the spinning wheel, and the lathe are all derived from the wheel. With the invention of self-propelled vehicles, the wheel began to act as a link in the propulsion system. Water wheels have been used in irrigation works, manufacturing mills, mines, and elsewhere. In the 19th century the the water wheel as an energy converter was gradually replaced by the turbine, which is also basically a wheel. In a majority of operating machines, the wheel alters the rotation speed, changes the direction of motion, or transfers motion from a horizontal axis to a vertical one or vice versa (in belt and gear drives and the like).
What does it mean when you dream about a wheel?
A wheel may indicate completion of a project or the continuation of a familiar situation. A circle is also a spiritual sign of that which has no beginning and no end. Alternatively, the dreamer may be caught in a situation in which he or she feels they are going in a circle.