| 释义 |
▪ I. intersect, v.|ɪntəˈsɛkt|
[f. L. intersect-, ppl. stem of intersecāre to cut asunder, intersect, f. inter between + secāre to cut.]
1. trans. To divide (something) in two by passing through or lying across it; to cross. Freq. in passive (const. with or by).
1615Crooke Body of Man 351 Why they are obliquely placed and intersect themselues Varolius hath elegantly shewd. 1713Pope Guardian No. 92 ⁋5 Tim Tuck, the hero..is particularly remarkable for the length of his sword, which intersects his person in a cross line, and makes him appear not unlike a fly, that the boys have run a pin thro' and set a walking. 1776Gibbon Decl. & F. xiii. I. 396 Four streets, intersecting each other at right angles. 1793Craufurd in Ld. Auckland's Corr. (1862) III. 132 The ground was so broken and intersected with ravines, that not a horseman could act. 1849Murchison Siluria iii. 38 It is often intersected by veins of quartz. 1860Tyndall Glac. i. xix. 135 Crevasses also intersect the ice.
b. Geom. Of a line or surface: To pass through or across (a line or surface), so as to lie on both sides of it with one point (or line) in common: = cut v. 15 b.
1646Sir T. Browne Pseud. Ep. vi. v. 292 Being in the æquator it would intersect their Horizon, and be halfe above and halfe beneath it. 1703Moxon Mech. Exerc. 269 Where these two Arches Intersect, or cut each other, there is the Center. 1840Lardner Geom. x. 125 If two chords intersect each other in a circle, the rectangle under the segments of the one will be equal to the rectangle under the segments of the other. 1858O. W. Holmes Aut. Breakf.-t. xii. 112 Keep any line of knowledge ten years, and some other line will intersect it. 1873B. Williamson Diff. Calc. (ed. 2) xiii. §190 Every [straight] line must intersect a curve of an odd degree in at least one real point.
c. Of a person: To come across, cross (another person, or his course); to intercept. rare.
1862Carlyle Fredk. Gt. ix. vi. (1872) III. 124 Grumkow, we suppose, drives forth from Berlin, to intersect him, in the Neumark. 1873Tristram Moab viii. 154 Shepherds hurriedly stalking forth ahead, so as to intersect our path.
d. To divide or separate (two things) by passing between them. rare.
1784Cowper Task ii. 16 Lands intersected by a narrow frith Abhor each other.
2. intr. (for refl.) To cross or cut each another: chiefly Geom. of lines or surfaces.
[1755in Johnson: quoting Wiseman in error: see interject.] 1847Grote Greece ii. xlvii. (1862) IV. 161 Straight streets intersecting at right angles. 1869Tyndall Notes Lect. Light 24 The rays from a luminous point placed beyond the focus intersect at the opposite side of the lens. 1873B. Williamson Diff. Calc. (ed. 2) xiv. §204 The Lemniscate whose equation is (x2 + y2)2 = a (x2 - y2)..[has] two branches intersecting at the origin.
b. Logic. (See quot.)
1864Bowen Logic iv. 93 Concepts are said to intersect, when the Extension of one coincides in part, and only in part, with the Extension of the other. Thus, Frenchman and Protestant are Intersecting Concepts, for some Frenchmen are Protestants and some are not, some Protestants are Frenchmen and some are not. These may be symbolized by two circles whose circumferences intersect each other.
▪ II. intersect, n.|ˈɪntəsɛkt|
[ad. L. intersect-um, neuter of pa. pple. of intersecāre: see prec.]
†1. = insect n. Obs.
1654H. L'Estrange Chas. I (1655) 74 Whilest he the head, and his subjects the body, were at a distance, or like intersects and flies, tacked together by a mathematical line, and imaginary thread.
2. Geom. A point of intersection.
1886Athenæum 19 June 815/1 Mr. Marth gave an account of his method of mapping the curves described by the intersects of the planetary orbits with a plane at right angles to the ecliptic. |