from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Mathematics A fixed curve traversed by a generatrix in generating a conic section or a cylinder.
- n. The median line in the trajectory of fire of an artillery piece.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A female who directs; a directress.
- n. A line used to define a curve or surface; especially a line, the distance from which a point on a conic has a constant ratio to that from the focus
from the GNU version of the Collaborative International Dictionary of English
- n. A directress.
- n. A line along which a point in another line moves, or which in any way governs the motion of the point and determines the position of the curve generated by it; the line along which the generatrix moves in generating a surface.
- n. A straight line so situated with respect to a conic section that the distance of any point of the curve from it has a constant ratio to the distance of the same point from the focus.
from The Century Dictionary and Cyclopedia
- n. A woman who governs or directs.
- n. In mathematics, a fixed line, whether straight or not, that is required for the description of a curve or surface.
- n. In gunnery, the center line in the plane of fire of an embrasure or platform. Tidball. See embrasure
- n. The first line traced on the ground in laying out a fortification.
Sorry, no etymologies found.