The Collaborative International Dictionary of English v.0.48:
Tension \Ten"sion\, n. [L. tensio, from tendere, tensum, to
stretch: cf. F. tension. See Tense, a.]
1. The act of stretching or straining; the state of being
stretched or strained to stiffness; the state of being
bent strained; as, the tension of the muscles, tension of
the larynx.
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2. Fig.: Extreme strain of mind or excitement of feeling;
intense effort.
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3. The degree of stretching to which a wire, cord, piece of
timber, or the like, is strained by drawing it in the
direction of its length; strain. --Gwilt.
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4. (Mech.) The force by which a part is pulled when forming
part of any system in equilibrium or in motion; as, the
tension of a srting supporting a weight equals that
weight.
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5. A device for checking the delivery of the thread in a
sewing machine, so as to give the stitch the required
degree of tightness.
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6. (Physics) Expansive force; the force with which the
particles of a body, as a gas, tend to recede from each
other and occupy a larger space; elastic force;
elasticity; as, the tension of vapor; the tension of air.
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7. (Elec.) The quality in consequence of which an electric
charge tends to discharge itself, as into the air by a
spark, or to pass from a body of greater to one of less
electrical potential. It varies as the quantity of
electricity upon a given area.
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Tension brace, or Tension member (Engin.), a brace or
member designed to resist tension, or subjected to
tension, in a structure.
Tension rod (Engin.), an iron rod used as a tension member
to strengthen timber or metal framework, roofs, or the
like.
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