from The Century Dictionary and Cyclopedia

  • n. A line dividing any symmetrical plane figure or surface of revolution into two symmetrical halves.
  • n. The line around which any figure may be revolved to generate a volume of revolution.
  • n. The line in a drawing on each side of which points in the diagram or figure lie at equal distances. In all designing of symmetrical constructions the center-lines are drawn first, and from these all dimensions are laid off.
  • n. plural The lines through the center of mass or center of gravity of a body parallel to the three coördinate axes used in analytical geometry.
  • n. The line joining the centers of two parallel shafts in the same plane, or perpendicular to both axes if they are not in the same plane, in the design of toothed gearing. See also line of center, under line.


Sorry, no etymologies found.



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