Tension

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.
2. Fig.: Extreme strain of mind or excitement of feeling; intense effort.
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.
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.
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.
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.
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.
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.