DICT.TW Dictionary Taiwan
Re·frac·tion n.
1. The act of refracting, or the state of being refracted.
2. The change in the direction of ray of light, heat, or the like, when it enters obliquely a medium of a different density from that through which it has previously moved.
Refraction out of the rarer medium into the denser, is made towards the perpendicular. --Sir I. Newton.
3. Astron. (a) The change in the direction of a ray of light, and, consequently, in the apparent position of a heavenly body from which it emanates, arising from its passage through the earth's atmosphere; -- hence distinguished as atmospheric refraction, or astronomical refraction. (b) The correction which is to be deducted from the apparent altitude of a heavenly body on account of atmospheric refraction, in order to obtain the true altitude.
Angle of refraction Opt., the angle which a refracted ray makes with the perpendicular to the surface separating the two media traversed by the ray.
Conical refraction Opt., the refraction of a ray of light into an infinite number of rays, forming a hollow cone. This occurs when a ray of light is passed through crystals of some substances, under certain circumstances. Conical refraction is of two kinds; external conical refraction, in which the ray issues from the crystal in the form of a cone, the vertex of which is at the point of emergence; and internal conical refraction, in which the ray is changed into the form of a cone on entering the crystal, from which it issues in the form of a hollow cylinder. This singular phenomenon was first discovered by Sir W. R. Hamilton by mathematical reasoning alone, unaided by experiment.
Differential refraction Astron., the change of the apparent place of one object relative to a second object near it, due to refraction; also, the correction required to be made to the observed relative places of the two bodies.
Double refraction Opt., the refraction of light in two directions, which produces two distinct images. The power of double refraction is possessed by all crystals except those of the isometric system. A uniaxial crystal is said to be optically positive (like quartz), or optically negative (like calcite), or to have positive, or negative, double refraction, according as the optic axis is the axis of least or greatest elasticity for light; a biaxial crystal is similarly designated when the same relation holds for the acute bisectrix.
Index of refraction. See under Index.
Refraction circle Opt., an instrument provided with a graduated circle for the measurement of refraction.
Refraction of latitude, longitude, declination, right ascension, etc., the change in the apparent latitude, longitude, etc., of a heavenly body, due to the effect of atmospheric refraction.
Terrestrial refraction, the change in the apparent altitude of a distant point on or near the earth's surface, as the top of a mountain, arising from the passage of light from it to the eye through atmospheric strata of varying density.
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Right a.
1. Straight; direct; not crooked; as, a right line. “Right as any line.”
2. Upright; erect from a base; having an upright axis; not oblique; as, right ascension; a right pyramid or cone.
3. Conformed to the constitution of man and the will of God, or to justice and equity; not deviating from the true and just; according with truth and duty; just; true.
That which is conformable to the Supreme Rule is absolutely right, and is called right simply without relation to a special end. --Whately.
2. Fit; suitable; proper; correct; becoming; as, the right man in the right place; the right way from London to Oxford.
5. Characterized by reality or genuineness; real; actual; not spurious. “His right wife.”
In this battle, . . . the Britons never more plainly manifested themselves to be right barbarians. --Milton.
6. According with truth; passing a true judgment; conforming to fact or intent; not mistaken or wrong; not erroneous; correct; as, this is the right faith.
You are right, Justice, and you weigh this well. --Shak.
If there be no prospect beyond the grave, the inference is . . . right, =\“Let us eat and drink, for to-morrow we die.”\= --Locke.
7. Most favorable or convenient; fortunate.
The lady has been disappointed on the right side. --Spectator.
8. Of or pertaining to that side of the body in man on which the muscular action is usually stronger than on the other side; -- opposed to left when used in reference to a part of the body; as, the right side, hand, arm. Also applied to the corresponding side of the lower animals.
Became the sovereign's favorite, his right hand. --Longfellow.
Note: ☞ In designating the banks of a river, right and left are used always with reference to the position of one who is facing in the direction of the current's flow.
9. Well placed, disposed, or adjusted; orderly; well regulated; correctly done.
10. Designed to be placed or worn outward; as, the right side of a piece of cloth.
At right angles, so as to form a right angle or right angles, as when one line crosses another perpendicularly.
Right and left, in both or all directions. [Colloq.]
Right and left coupling Pipe fitting, a coupling the opposite ends of which are tapped for a right-handed screw and a left-handed screw, respectivelly.
Right angle. (a) The angle formed by one line meeting another perpendicularly, as the angles ABD, DBC. (b) Spherics A spherical angle included between the axes of two great circles whose planes are perpendicular to each other.
Right ascension. See under Ascension.
Right Center Politics, those members belonging to the Center in a legislative assembly who have sympathies with the Right on political questions. See Center, n., 5.
Right cone, Right cylinder, Right prism, Right pyramid Geom., a cone, cylinder, prism, or pyramid, the axis of which is perpendicular to the base.
Right line. See under Line.
Right sailing Naut., sailing on one of the four cardinal points, so as to alter a ship's latitude or its longitude, but not both. --Ham. Nav. Encyc.
Right sphere Astron. & Geol., a sphere in such a position that the equator cuts the horizon at right angles; in spherical projections, that position of the sphere in which the primitive plane coincides with the plane of the equator.
Note: ☞ Right is used elliptically for it is right, what you say is right, true.
=\“Right,” cries his lordship.\= --Pope.
Syn: -- Straight; direct; perpendicular; upright; lawful; rightful; true; correct; just; equitable; proper; suitable; becoming.
As·cen·sion, n.
1. The act of ascending; a rising; ascent.
2. Specifically: The visible ascent of our Savior on the fortieth day after his resurrection. (--Acts i. 9.) Also, Ascension Day.
3. An ascending or arising, as in distillation; also that which arises, as from distillation.
Vaporous ascensions from the stomach. --Sir T. Browne.
Ascension Day, the Thursday but one before Whitsuntide, the day on which commemorated our Savior's ascension into heaven after his resurrection; -- called also Holy Thursday.
Right ascension Astron., that degree of the equinoctial, counted from the beginning of Aries, which rises with a star, or other celestial body, in a right sphere; or the arc of the equator intercepted between the first point of Aries and that point of the equator that comes to the meridian with the star; -- expressed either in degrees or in time.
Oblique ascension Astron., an arc of the equator, intercepted between the first point of Aries and that point of the equator which rises together with a star, in an oblique sphere; or the arc of the equator intercepted between the first point of Aries and that point of the equator that comes to the horizon with a star. It is little used in modern astronomy.
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right ascension
n 1: (astronomy) the angular distance eastward along the
celestial equator from the vernal equinox to the
intersection of the hour circle that passes through the
body; expressed in hours and minutes and second; used
with declination to specify positions on the celestial
sphere; "one hour of right ascension equals fifteen
degrees" [syn: RA, celestial longitude]
2: an arc of the celestial equator eastward from the vernal
equinox