[f. L. co- + ordināt-us ordered, arranged, pa. pple. of ordināre to order; prob. formed as a parallel to subordinate. Cf. mod.F. coordonné. But in some senses it is analysed as CO- + ORDINATE.]
1. Of the same order; equal in rank, degree, or importance (with); opposed to subordinate. In Gram. used esp. of the clauses of a compound sentence.
1641. R. Brooke, Eng. Episc., II. vii. 106. All these Churches are but Coordinate, not among themselves Subordinate.
1677. Gale, Crt. Gentiles, II. IV. 23. He is placed beneath God, coordinate with intellectual creatures, but above corporeous creatures.
1794. Paley, Evid., II. vi. § 23. Annas possessed an authority co-ordinate with or next to that of the high-priest properly so called.
1832. J. C. Hare, in Philol. Mus., I. 648. The formal laws of our understanding are not coordinate to the infinite variety of nature.
1846. Trench, Mirac., xv. (1862), 250. Instead of three being thus subordinated to one, all four are coordinate with one another.
1864. Bowen, Logic, iv. 91. Two or more Species are thus said to be Coordinate when each excludes the other from its own Extension, but both or all are included under the Extension of the same nearest higher Concept.
1871. Public Sch. Lat. Gram., § 151. A Coordinate Clause is not governed in its construction by the Principal Sentence.
1876. Mason, Eng. Gram., 163. A compound sentence is one which consists of two or more co-ordinate principal sentences, joined together by co-ordinative conjunctions.
2. Proceeding in a corresponding order.
1794. Sullivan, View Nat., I. 414. The phases of the moon are co-ordinate with the course of the sun.
3. Involving coordination; consisting of a number of things of equal rank, or of a number of actions or processes properly combined for the production of one result.
1769. Robertson, Chas. V., III. VIII. 91. All the inconveniences arising from a divided and co-ordinate jurisdiction.
1876. Foster, Phys., III. vii. (1879), 605. So complex and co-ordinate a movement.
B. sb.
1. One who or that which is coordinate, or of the same rank; an equal; a coordinate element.
a. 1850. Calhoun, Wks. (1874), II. 397. The great fundamental division of the powers of the system, between this government and its independent coordinates, the separate governments of the states.
1879. Tourgee, Fool’s Err., xlv. 343. Can the African slave … develop into the self-governing citizen, the co-ordinate of his white brother in power.
2. Math. Each of a system of two or more magnitudes used to define the position of a point, line, or plane, by reference to a fixed system of lines, points, etc. (Usually in pl.)
In the original (and most often used) system, invented by Descartes, and hence known as that of Cartesian coordinates, the coordinates of a point (in a plane) are its distances from two fixed intersecting straight lines (the axes of coordinates), the distance from each axis being measured in a direction parallel to the other axis. (The determination of the position of a place by latitude and longitude is a similar case.) The coordinates are rectangular when the axes are at right angles; otherwise oblique. The name Cartesian coordinates is also extended to the case of points in space (not in a particular plane) referred to three axes not in one plane intersecting in a point (like three edges of a box meeting at one corner).
Hence applied to various other systems, mostly named from the nature of the fixed figure, etc., to which the points are referred; as Bipunctual coordinates, coordinates defining a line or point by reference to two fixed points and a fixed direction. Polar coordinates, coordinates defining a point (in a plane) by reference to a fixed line (initial line or axis) and a fixed point (origin or pole) in that line; the coordinates of any point being the length of the straight line (radius vector) drawn to it from the pole, and the angle which this line makes with the axis (as in defining the position of a place by its distance and bearing from a given place). The name polar coordinates is also applied to an extension of this system to points in space. So bicircular coordinates, bilinear c., trilinear c., etc.
1823. Crabb, Technol. Dict., Co-ordinates (Geom.), a term applied to the absciss and ordinates when taken in connexion.
1855. Tylor, Early Hist. Man., iv. 60. He can in thought shift his centre of co-ordinates and the position of his axes.
1879. Thomson & Tait, Nat. Phil., I. I. § 202. The most general system of co-ordinates of a point consists of three sets of surfaces, on one of each of which it lies.
b. attrib. Pertaining to or involving the use of coordinates.
1855. Todhunter (title), Treatise on Plane Co-ordinate Geometry.
