| 释义 |
octant
oc·tant O0027100 (ŏk′tənt)n.1. One eighth of a circle.2. a. A 45° arc.b. The area enclosed by two radii at a 45° angle and the intersected arc.3. An instrument based on the principle of the sextant but employing only a 45° angle, used as an aid in navigation.4. Astronomy The position of a celestial body when it is separated from another by a 45° angle.5. One of eight parts into which three-dimensional space is divided by three usually perpendicular coordinate planes.
[Latin octāns, octant-, from octō, eight; see oktō(u) in Indo-European roots.]
oc·tan′tal (ŏk-tăn′təl) adj.octant (ˈɒktənt) n1. (Mathematics) maths a. any of the eight parts into which the three planes containing the Cartesian coordinate axes divide spaceb. an eighth part of a circle2. (Astronomy) astronomy the position of a celestial body when it is at an angular distance of 45° from another body3. (Navigation) an instrument used for measuring angles, similar to a sextant but having a graduated arc of 45°[C17: from Latin octans half quadrant, from octo eight]oc•tant (ˈɒk tənt)
n. 1. the eighth part of a circle. 2. any of the eight parts into which three mutually perpendicular planes divide space. 3. an instrument having an arc of 24°, used by navigators for measuring angles up to 90°. 4. the position of one heavenly body when 45° distant from another. [1680–90; < Latin octant-, s. of octāns=oct(ō) eight + -āns, as in quadrāns quadrant] oc•tan′tal (-ˈtæn tl) adj. Thesaurus| Noun | 1. |  octant - a measuring instrument for measuring angles to a celestial body; similar to a sextant but with 45 degree calibrationlimb - the graduated arc that is attached to an instrument for measuring angles; "the limb of the sextant"measuring device, measuring instrument, measuring system - instrument that shows the extent or amount or quantity or degree of something |
Translationsoctant
octant[′äk·tənt] (mathematics) One of the eight regions into which three-dimensional Euclidean space is divided by the coordinate planes of a Cartesian coordinate system. A unit of plane angle equal to 45° or π/8 radians. (navigation) A double-reflecting instrument used primarily for measuring altitudes of celestial bodies from a moving ship or airplane; has a range of 90°, and while a sextant has the capability up to 120°, the common practice applies the name sextant to both types of instruments.
Octant[′äk·tənt] (astronomy) Octans Octant a goniometric instrument whose main component is an arc that forms one-eighth of a circle and is divided into degrees and fractions of a degree. Instruments similar in design to sextants are usually called octants. Octants have almost completely fallen out of use. octant  When an aircraft accelerates, inertia causes the otolith membrane in a pilots' otolith organ to move. This results in the sensation of climbing and might cause the pilot to push the stick forward and dive. The reverse would occur in case of deceleration.An instrument similar to a bubble sextant but constructed with its arc graduated in degrees for an eighth of a circle. Frequently called a sextant. An octant can measure angles up to 90°.octant
Words related to octantnoun a measuring instrument for measuring angles to a celestial bodyRelated Words- limb
- measuring device
- measuring instrument
- measuring system
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