| 释义 |
quad·rant
I. \ˈkwädrənt sometimes ˈkwȯd-\ noun
(-s)
Etymology: Middle English, from Latin quadrant-, quadrans fourth part, quarter; akin to Latin quattuor four — more at four
1. : something shaped like a quarter-circle: as
a. : an instrument for measuring altitudes variously constructed and mounted for different specific uses (as in astronomy, surveying, gunnery) and consisting commonly of a graduated arc of 90° with an index or vernier and either plain or telescopic sights and usually having a plumb line or spirit level for fixing the vertical or horizontal direction
b. : a device resembling a bell crank for converting the horizontal reciprocating motion of an engine piston rod into the vertical up-and-down movement of a pump rod
c. : a dial or an indexing sector of approximate quarter-circle range; also : a lever that moves over such a range
d. : a device on a spinning mule for controlling the winding of the yarn
2.
a. : a quarter of a circle, an arc of 90°, or an arc subtending a right angle at the center
b. : the area bounded by a quadrant and two radii
3.
a. : any of the four parts into which a plane is divided by rectangular coordinate axes lying in that plane
b. : any of the four more or less equal parts into which something is divided by two real or imaginary lines that intersect each other at right angles
< located in the upper left quadrant of a page >
< a building in the southeast quadrant of the city >
< most hurricanes … are not symmetrical — the winds are much stronger in some quadrants — R.C.Gentry & R.H.Simpson >
c. : a group comprising all the cells resulting from divisions of one of the first four blastomeres in spirally cleaving eggs with determinate cleavage
d. : any of four more or less equivalent segments into which an anatomic structure or surface may be divided by vertical and horizontal partitioning through its midpoint — used chiefly of the abdomen
< severe pain in the lower right quadrant >
e. : the sector between the equisignal zones of a four-course aural radio range
 [quadrant 2]
II. adjective
Etymology: probably alteration (influenced by quadrant) (I) of quadrate (I)
obsolete : square, quadrate |