polar

American Heritage® Dictionary of the English Language, Fourth Edition

1. adj. Of or relating to a pole.
2. adj. Measured from or referred to a pole: polar distance; polar diameter.
3. adj. Relating to, connected with, or located near the North Pole or South Pole.
4. adj. Passing over a planet's north and south poles: a polar orbit.
5. adj. Traveling in an orbit that passes over a planet's north and south poles.
6. adj. Serving as a guide, as a polestar or a pole of the earth.
7. adj. Occupying or characterized by opposite extremes: "In creative territory [they] make a strange yet ineluctable couple, more complementary, even polar, than twin-like” ( Josh Rubins).
8. adj. Central or pivotal.
9. adj. Chemistry Relating to or characterized by a dipole: a polar molecule.
10. adj. Ionizing when dissolved or fused: polar bonds or linkages.

Century Dictionary and Cyclopedia

1. Of or pertaining to a pole or the poles of a sphere. Of or pertaining to either extremity of the axis round which the earth, or any other sphere, revolves
2. Proceeding, issuing from, or found in the regions near the poles of the earth or of the heavens: as, the polar ocean; a polar bear.
3. Pertaining to a magnetic pole or poles; pertaining to the points of a body at which its attractive or repulsive energy is concentrated.
4. In anatomy, having poles in any way distinguished, as a cell: said especially of ovum-cells and nerve-cells. There may be one, two, or several poles, when the cell is distinguished as unipolar, bipolar, or multipolar.
5. In higher geom., reciprocal to a pole; of the nature of a polar. See II.
6. n. A plane curve whose point-equation is derived from that of another plane curve (with respect to which it is said to be a polar) by operating one or more times (according as it is first, second, etc., polar) with the symbol x′ . d/ d x + y'. d/ d y + z'. d/ d z, where x', y', z' are the trilinear coördinates of a fixed point (of which the curve is said to be a polar). The first polar of a point with respect to a curve is a curve of the next lower order, cutting the primitive curve at all the points of tangency of tangents to the primitive from the fixed point, as well as at all the nodes of the primitive, and tangent to the primitive at every cusp of the latter. Thus, the polar of a point with respect to a conic is simply the straight line joining the points of tangency of tangents from that point to the conic. The harmonic mean of the distances from the fixed point, measured along any given radius of the intersections of any polar of that point, is the same as that of the distances of the intersections of the primitive curve; and the same is equally true of products of pairs or triplets or any number of intersections. In a generalized sense, mathematicians speak of a polar of a curve with respect to another curve: if the tangential equation of the first curve is (a, b, c, … u, v, w), and the pointequation of the second curve is (A, B, C, … x, y, z), where m ⟩ s, then the polar of the first with respect to the second is But if s ⟩ m, the polar of the second curve with respect to the first is
7. Having opposite properties at its two ends.
8. n. A great circle two of whose points are each a quadrant from a given point: it is the polar of the given point.
9. n. Given a trihedral; to each face from the vertex erect a perpendicular ray on the same side as the third edge; the trihedral they form is the polar of the given one.

Wiktionary

1. adj. of, relating to, measured from, or referred to a geographic pole (the North Pole or South Pole)
2. adj. of an orbit that passes over, or near, one of these poles
3. adj. chemistry having a dipole; ionic
4. adj. mathematics of a coordinate system, specifying the location of a point in a plane by using a radius and an angle
5. adj. linguistics, of a question Having but two possible answers, yes and no.

GNU Webster's 1913

1. adj. Of or pertaining to one of the poles of the earth, or of a sphere; situated near, or proceeding from, one of the poles
2. adj. Of or pertaining to the magnetic pole, or to the point to which the magnetic needle is directed.
3. adj. (Geom.) Pertaining to, reckoned from, or having a common radiating point.
4. n. (Conic Sections) The right line drawn through the two points of contact of the two tangents drawn from a given point to a given conic section. The given point is called the pole of the line. If the given point lies within the curve so that the two tangents become imaginary, there is still a real polar line which does not meet the curve, but which possesses other properties of the polar. Thus the focus and directrix are pole and polar. There are also poles and polar curves to curves of higher degree than the second, and poles and polar planes to surfaces of the second degree.

WordNet 3.0

1. adj. characterized by opposite extremes; completely opposed
2. adj. being of crucial importance
3. adj. located at or near or coming from the earth's poles
4. adj. extremely cold
5. adj. of or existing at or near a geographical pole or within the Arctic or Antarctic Circles
6. adj. having a pair of equal and opposite charges