From The Collaborative International Dictionary of English v.0.48:
Cam \Cam\ (k[a^]m), n. [Dan. kam comb, ridge; or cf. W., Gael.,
and Ir., cam bent. See 1st Comb.]
1. (Med.)
(a) 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.
(b) A curved wedge, movable about an axis, used for
forcing or clamping two pieces together.
(c) 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.
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Note: Cams are much used in machinery involving complicated,
and irregular movements, as in the sewing machine, pin
machine, etc.
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2. A ridge or mound of earth. [Prov. Eng.] --Wright.
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Cam wheel (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.
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From The Collaborative International Dictionary of English v.0.48:
Cam \Cam\, a. [See Kam.]
Crooked. [Obs.]
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