英文字典中文字典


英文字典中文字典51ZiDian.com



中文字典辞典   英文字典 a   b   c   d   e   f   g   h   i   j   k   l   m   n   o   p   q   r   s   t   u   v   w   x   y   z       







请输入英文单字,中文词皆可:

quadrant    音标拼音: [kw'ɑdrənt]
n. 四分圆,象限,四分仪

四分圆,象限,四分仪

quadrant
象限 QUAD

quadrant
象限

quadrant
n 1: a quarter of the circumference of a circle [synonym:
{quadrant}, {quarter-circle}]
2: any of the four areas into which a plane is divided by two
orthogonal coordinate axes
3: the area enclosed by two perpendicular radii of a circle
4: a measuring instrument for measuring altitude of heavenly
bodies

Octant \Oc"tant\, n. [L. octans, -antis. fr. octo eight. See
{Octave}.]
1. (Geom.) The eighth part of a circle; an arc of 45 degrees.
[1913 Webster]

2. (Astron. & Astrol.) The position or aspect of a heavenly
body, as the moon or a planet, when half way between
conjunction, or opposition, and quadrature, or distant
from another body 45 degrees.
[1913 Webster]

3. An instrument for measuring angles (generally called a
{quadrant}), having an arc which measures up to 9O[deg],
but being itself the eighth part of a circle. Cf.
{Sextant}.
[1913 Webster]

4. (Math. & Crystallog.) One of the eight parts into which a
space is divided by three coordinate planes.
[1913 Webster]


Quadrant \Quad"rant\, n. [L. quadrans, -antis, a fourth part, a
fourth of a whole, fr. quattuor four: cf. F. quadrant,
cadran. See {Four}, and cf. {Cadrans}.]
1. The fourth part; the quarter. [Obs.] --Sir T. Browne.
[1913 Webster]

2. (Geom.) The quarter of a circle, or of the circumference
of a circle, an arc of 90[deg], or one subtending a right
angle at the center.
[1913 Webster]

3. (Anal. (Geom.) One of the four parts into which a plane is
divided by the coordinate axes. The upper right-hand part
is the first quadrant; the upper left-hand part the
second; the lower left-hand part the third; and the lower
right-hand part the fourth quadrant.
[1913 Webster]

4. An instrument for measuring altitudes, variously
constructed and mounted for different specific uses in
astronomy, surveying, gunnery, etc., consisting commonly
of a graduated arc of 90[deg], 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.
[1913 Webster]

{Gunner's quadrant}, an instrument consisting of a graduated
limb, with a plumb line or spirit level, and an arm by
which it is applied to a cannon or mortar in adjusting it
to the elevation required for attaining the desired range.


{Gunter's quadrant}. See {Gunter's quadrant}, in the
Vocabulary.

{Hadley's quadrant}, a hand instrument used chiefly at sea to
measure the altitude of the sun or other celestial body in
ascertaining the vessel's position. It consists of a frame
in the form of an octant having a graduated scale upon its
arc, and an index arm, or alidade pivoted at its apex.
Mirrors, called the index glass and the horizon glass, are
fixed one upon the index arm and the other upon one side
of the frame, respectively. When the instrument is held
upright, the index arm may be swung so that the index
glass will reflect an image of the sun upon the horizon
glass, and when the reflected image of the sun coincides,
to the observer's eye, with the horizon as seen directly
through an opening at the side of the horizon glass, the
index shows the sun's altitude upon the scale; -- more
properly, but less commonly, called an octant.

{Quadrant of altitude}, an appendage of the artificial globe,
consisting of a slip of brass of the length of a quadrant
of one of the great circles of the globe, and graduated.
It may be fitted to the meridian, and being movable round
to all points of the horizon, serves as a scale in
measuring altitudes, azimuths, etc.
[1913 Webster]

51 Moby Thesaurus words for "quadrant":
adjunct, astrolabe, azimuth circle, azimuth compass, bevel,
bevel protractor, bevel square, clinometer, component, contingent,
crescent, cross section, detachment, detail, division, dole,
fraction, goniometer, graphometer, half circle, hemicycle,
installment, item, pantometer, parcel, part, particular,
percentage, portion, protractor, quarter, quota, radiogoniometer,
random sample, remainder, sample, sampling, section, sector,
segment, semicircle, sextant, share, subdivision, subgroup,
subspecies, theodolite, transit, transit circle,
transit instrument, transit theodolite



安装中文字典英文字典查询工具!


中文字典英文字典工具:
选择颜色:
输入中英文单字

































































英文字典中文字典相关资料:


  • Online Stopwatch - easy to use - timeanddate. com
    Online Stopwatch, with start alerts, lap times and sounds Save details of your timings in a text file
  • Online Timer with Alarm - timeanddate. com
    Timer online with alarm Create one or multiple timers and start them in any order Set a silent timer clock or choose a sound
  • Online Stopwatch - How to Use it - Support - timeanddate. com
    A free, easy to use stopwatch with start alerts, split times and intervals Edit laps with a single click and without interrupting the timer Keep track of lap times by recording splits in a text file Use it for sports, cooking, work or school
  • FAQ: Online Stopwatch - timeanddate. com
    Free, simple online stopwatch with start alerts, lap times, and sounds Time your activities and save your timings in a text file
  • timeanddate. com
    Stopwatch Timer Countdown to Any Date Easter Countdown Summer Countdown New Year Countdown Countdown for Your Site Calculators Date to Date Calculator (duration) Business Date to Date (exclude holidays) Date Calculator (add subtract) Business Date (exclude holidays) Weekday Calculator Week Number Calculator Roman Numeral Converter Alternative
  • Countdown Timer to Any Date
    Create a Countdown Timer that counts down in seconds, minutes, hours and days to any date, with time zone support It also counts up from a past date
  • Date Calculator: Add to or Subtract From a Date
    Date Calculator: Add to or Subtract From a Date Enter a start date and add or subtract any number of days, months, or years
  • Timers Countdowns Overview - timeanddate. com
    Explore our online timers and countdown tools Create your own countdown or use our pre-made countdowns to popular events
  • Millennium (year 2001) information - timeanddate. com
    Millennium (2001) information When Did the 21st Century Start? Why is 2001, and not 2000, the start of the third millennium? Many people think that the 3rd Millennium and 21st century started in year 2000 This is a popular misconception The millennium formally started on 1 January 2001
  • Sunrise and sunset times in Bago, August 2026
    Calculations of sunrise and sunset in Bago – Tirana – Albania for August 2026 Generic astronomy calculator to calculate times for sunrise, sunset, moonrise, moonset for many cities, with daylight saving time and time zones taken in account





中文字典-英文字典  2005-2009