An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



Number of Results: 15 Search : bow
  ۱) کمان؛ ۲) فرال   
1) kamân; 2) farâl

Fr.: proue   

1a) A bent, curved, or arched object.
1b) A weapon made of a curved, flexible strip of material and a cord connecting the two ends that is used to launch an arrow. 2) The front of a ship or boat; prow; opposite to stern or poop, → Puppis.

1) M.E., from O.E. boga "archery bow, arch, rainbow" (cf. O.Norse bogi, Du. boog, Ger. Bogen "bow"); PIE root *bheug- "to bend;" cf. Skt. bhujati "bends;" O.H.G. boug, O.E. beag "a ring").
2) M.E. boue, from O.N. bogr or M.Du. boech "bow of a ship."

1) Kamân "bow, arc," from Mid.Pers. kamân, related to xam "curve," cf. Breton kamm "curved, bent," Gk. kampe "a corner, a joint," L. campus "a field," Lith. kampus "corner," PIE *kamb- "to bend, crook." Farâl, from farâ "forward" (farâ raftan "to go forward, proceed," farâ rândan "to drive forward"), equivalent to → pro-, + relation suffix -âl, → -al. Compare farâl with prow "bow," Fr. la proue "prow, bow," from dialectal It. proa, prua, from L. prora "bow," from Gk. proira, related to pro "before, forward."

bow shock
  فرال-تش، فرال-شوک   
farâl-toš farâl-šok

Fr.: choc de proue   

A → shock wave created in front of an object moving through a medium with a velocity higher than that of the → sound waves in that medium. See, for example, → magnetosphere.

bow; → shock.

bow wave
  فرال-موج، موج ِ فرال   
farâl-mowj, mowj-e farâl

Fr.: onde de proue   

The wave which appears in front of a speeding boat and goes out behind it in a distinctive "V". It is due to the fact that waves pile up on each other before they can move away.

bow; → wave.

Bowen fluorescence mechanism
  ساز-و-کار ِ فلوءورستی ِ باؤن   
sâzokâr-e fluoresti-ye Bowen

Fr.: mécanisme de fluorescence de Bowen   

A mechanism, made possible by certain chance coincidences between → spectral lines of He II, O III and N III in some → planetary nebulae , that explains the presence with a high intensity of a selected group of O III and N III lines while all other lines of these elements are missing.

After I. S. Bowen who first discovered this mechanism in 1935; → fluorescence; → mechanism.



A large, faintly colored arc formed usually by sunlight falling on a cloud. Also called white rainbow, fogbow, and mistbow. Cloudbow appears white because the water droplets in the cloud or fog are very small compared with those of ordinary rainbows.

cloud; → bow.

šabnam kamân


A rainbow formed in the small drops often found on grass in early morning. While the name implies that those drops are dew, that is probably rarely the case. Rather, the drops are usually the result of guttation (the water exuded from leaves as a result of root pressure) rather than dew.

dew; → bow.

ârenj (#)

Fr.: coude   

The joint of the human → arm between the → upper arm and the → forearm.

M.E. elbowe, from O.E. elboga, elnboga, from ell + bow. Cognate with Scots elbuck, Du. elleboog, Ger. Ellbogen, Ellenbogen, Dan. albue, Icelandic olbogi, olnbogi "elbow."

Ârenj "elbow," variants âranj, âran "elbow," araš "forearm;" Mid.Pers. âranj, O.Pers. arašan- "cubit," Av. arəθnâ- "elbow," Skt. aratni- "elbow," Iranian stem aratan-, araθn-, borrowed from Iranian into General Slavic as aršin "ell."


Fr.: arc blanc   

A large, faintly colored, circular arc formed by light (usually sunlight) falling on cloud or fog. Also called → cloudbow.

fog; → bow.


Fr.: arc en ciel lunaire   

A rainbow that arises from the refraction and reflection of moonlight on rain drops or mist.

moon; → bow.

primary rainbow
  رنگین‌کمان ِ نخستان   
rangin-kamân-e naxostân

Fr.: arc-en-ciel primaire   

The main rainbow that forms between about 40° and 42° from the → antisolar point (or about 50° from the → antisolar point), as viewed by the observer. The light path involves → refraction and a → single  → reflection inside the water → droplet. If the drops are large, 1 millimeter or more in diameter, red, green, and violet are bright but there is little blue.

As the droplets get smaller, red weakens.

Rainbows are not seen in midday since the whole 42° circle is below the horizon at most latitudes. So rainbows tend to be seen most in the later afternoon when a thundershower has passed and the Sun is illuminating from the west.

primary; → rainbow.

rangin kamân (#)

Fr.: arc-en-ciel   

A color effect produced by the → refraction and → internal reflection of sunlight passing through a mist of tiny spherical water → droplets in the air. The effect is visible only when the observer has his back to the Sun. It appears as a colored band at about 138° from the Sun, hence 42° from the → antisolar pint. In other words, 42° is the angle between the direction of the → incident sunlight and the → line of sight. The → primary rainbow is caused from one reflection inside water droplets; the red color appears on the top and violet on the bottom. At solar elevations higher than 42° the bow is entirely below the → horizon and therefore invisible in the sky. A full rainbow is actually a complete circle, but from the ground we see only part of it. From an airplane, in the right conditions, one can see an entire circular rainbow. A → secondary rainbow appears if the sunlight is reflected twice inside the water droplets. Secondary rainbows are fainter, and the order of the color is reversed, with red on the bottom and violet on the top. See also: → Alexander's dark band, → supernumerary rainbow.

From → rain; → bow.

rainbow angle
  زاویه‌ی ِ رنگین‌کمان   
zâviye-ye rangin-kamân

Fr.: angle d'arc-en-ciel   

The → obtuse angle between sunlight and the → line of sight. Rainbow angle = 180° minus → scattering angle. For the → primary rainbow it is 138°, and for the → secondary rainbow 130°.

rainbow; → angle.

rainbow ray
  پرتو ِ رنگین‌کمان   
partow-e rangin-kamân

Fr.: rayon d'arc-en-ciel   

The sunlight incident on a tiny spherical droplet of water.

rainbow; → ray.

secondary rainbow
  رنگین‌کمان ِ دومان   
rangin-kamân-e dovomân

Fr.: arc-en-ciel secondaire   

A fainter rainbow appearing about 10° above the → primary rainbow, as viewed by the observer. The secondary rainbow is about twice as wide, and has its colors reversed.

secondary; → rainbow.

supernumerary rainbow
  رنگین‌کمان ِ فرشمار   
rangin-kamân-e faršomâr

Fr.: arc-en-ciel surnuméraire   

An additional faint arc or series of arcs just below the → primary rainbow. Supernumerary bows are caused by → interference and are more common toward the top of the bow.

supernumerary; → rainbow.