cam

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A wheel that has a projecting part and is mounted on a rotating shaft to produce variable or reciprocating motion in another part.

from The Century Dictionary.

• Crooked; bent or bending.
• noun A comb.
• noun A ridge, hedge, or long earthen mound.
• noun In machinery, a device for converting a regular rotary motion into an irregular, fast and slow, intermittent rotary or reciprocating motion. It properly includes the cam-wheel, plain or geared, the cam-shaft, the heart-wheel, the wiper, the wiper-wheel, and the eccentric. The simplest form is that of a heart-shaped, lobe-shaped, or otherwise eccentric wheel, which imparts motion to another wheel either by means of gearing or by rolling contact. Instead of following the irregular face of the cam-wheel, the friction-wheel may travel in a curved race or guiding path on the side of a cam-disk, as in the cam-wheel of a harvester. In another form of cam the face of the wheel is cut into gears or into projecting teeth that may engage another gear, or an arm or a pinion upon a shaft, to give a quickly changing rising and falling motion. Such cams are also called wiper-wheels, and are used to operate stamps and tilt-hammers. The heart-wheel accomplishes the same object, but In a less abrupt manner, while eccentric cams of various shapes may impart a slow thrust and quick return, as in many machine-tools. The wiper, a cam-shaped arm, is very generally used to operate the valves of beam-engines. The cam in some of its forms appears in a great variety of machines, wherever an irregular speed or motion or a rapid reciprocating motion is required, as in the harvester, printing-press, sewing-machine, etc. A cam-shaft is a shaft having tumblers or wipers. The heart-wheel is a heart-shaped cam. (See eccentric.) Cams for determining motion for cutting and tracing, as in certain machines, are called shaper-plates.

from the GNU version of the Collaborative International Dictionary of English.

• noun A turning or sliding piece which, by the shape of its periphery or face, or a groove in its surface, imparts variable or intermittent motion to, or receives such motion from, a rod, lever, or block brought into sliding or rolling contact with it.
• noun A curved wedge, movable about an axis, used for forcing or clamping two pieces together.
• noun A projecting part of a wheel or other moving piece so shaped as to give alternate or variable motion to another piece against which it acts.
• noun Prow. Eng. A ridge or mound of earth.
• noun (Mach.) a wheel with one or more projections (cams) or depressions upon its periphery or upon its face; one which is set or shaped eccentrically, so that its revolutions impart a varied, reciprocating, or intermittent motion.
• adjective obsolete Crooked.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A turning or sliding piece which imparts motion to a rod, lever or block brought into sliding or rolling contact with it.
• noun rock climbing A camming device, a spring-loaded device for effecting a temporary belay in a rock crevice.
• noun informal camera
• verb To go on webcam with someone
• adverb Alternative form of kam.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a river in east central England that flows past Cambridge to join the Ouse River
• noun a rotating disk shaped to convert circular into linear motion