An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

The condition of a system in which the damping is so large that the system comes to a position of rest without oscillating.

→ over-; → damping.

Matter whose density exceeds a reference level.

→ over-; → dense; → matter.

1) To estimate at too high a value, amount, rate, or the like.
2) An estimate that is too high.

→ over-; → estimate.

In computers, the condition arising when the result of an arithmetic operation exceeds the capacity of the number representation.

→ over-; → flow.

Sarriz, from sar, → head, + riz present stem of rixtan "to flow, to pour" (Mid.Pers. rēxtan and rēcitan "to flow;" Av. raēk- "to leave, set free; to yield, transfer," infinitive *ricyā; Mod.Pers; rig in morderig "heritage" (literally, "left by the dead"); cf. Skt. rinakti "he leaves," riti- "stream; motion, course;" L. rivus "stream, brook;" Old Church Slavic rēka "river;" Rus. reka "river;" Goth. rinnan "run, flow," rinno "brook;" O.E. ridh "stream").

The part of observing time at a telescope which is not directly used for science, such as the time spent for detector read-out, changing instruments, focusing, etc.

→ over-; → head; → time.

Bâlâ "up, above, high, elevated, height" (variants boland "high, tall, elevated, sublime," borz "height, magnitude" (it occurs also in the name of the mountain chain Alborz), Laki dialect berg "hill, mountain;" Mid.Pers. buland "high;" O.Pers. baršan- "height;" Av. barəz- "high, mount," barezan- "height;" cf. Skt. bhrant- "high;" L. fortis "strong" (Fr. and E. force); O.E. burg, burh "castle, fortified place," from P.Gmc. *burgs "fortress;" Ger. Burg "castle," Goth. baurgs "city," E. burg, borough, Fr. bourgeois, bourgeoisie, faubourg; PIE base *bhergh- "high") + sar, → head.

1) (v.tr.) To lap over something else; extend over and cover a part of.
2) (v.intr.) To lap over.
3a) Math.: Of sets, to have one or more elements in common.
3b) Chemistry: The interaction of orbitals on different atoms in the same region of space.
3c) Meteo.: The area common to two successive satellite images or scan swaths along the same or adjacent flight or orbital strips. The amount of overlap is expressed as a percentage of image area or scanned area.

→ over- + lap, verb from noun lap, from O.E. læppa "skirt or flap of a garment," from P.Gmc. *lapp- (cf. M.Du. lappe, O.H.G. lappa, Ger. Lappen "rag, shred").

1) Barham nehâdan, from barham "one over the other" (for etymology of bar-, → on-; for etymology of ham-, → com-) + nehâdan "to place, put; to set" (Mid.Pers. nihâtan; Av. ni- "down; below; into," → ni-, + dā- "to put; to establish; to give," dadāiti "he gives;" cf. Skt. dadāti "he gives;" Gk. didomi "I give;" L. do "I give;" PIE base *do- "to give").
2) Barham nešastan, from barham, as above, + nešastan "to sit;" Mid.Pers. nišastan "to sit;" O.Pers. nišādayam [1 sg.impf.caus.act.] "to sit down, to establish," hadiš- "abode;" Av. nišasiiā [1 sg.subj.acr.] "I shall sit down," from nihad- "to sit down," from ni-, as above, + had- "to sit;" PIE base *sed- "to sit;" cf. Skt. sad- "to sit," sidati "sits;" Gk. hezomai "to sit," hedra "seat, chair;" L. sedere "to sit;" O.Ir. suide "seat, sitting;" Welsh sedd "seat;" Lith. sedmi "to sit;" Rus. sad "garden;" Goth. sitan, Ger. sitzen; E. sit.
3) → overlapping.

An act or instance related to → overlap.

Verbal noun of → overlap.

Electricity: Any load which exceeds the rated output of a machine, transformer, or other apparatus.

→ over-; → load.

Too highly qualified for a particular job (OxfordDictionaries.com).

→ over-; → qualified.

The process of sampling a signal with a frequency higher than the → Nyquist frequency. The signal is said to be oversampled β times, where the oversampling ratio is defined as β = (sampling frequency)/(Nyquist frequency).

→ over-; → sampling.

A situation in stellar interiors when the momentum of a particle carries it past its equilibrium point.

→ over-; shooting, from shoot, from O.E. sceotan "to shoot" (cf. O.N. skjota, Du. schieten, Ger. schießen), from PIE base *skeud- "to shoot, to chase, to throw, to project."

Farâzad, from farâ- "over, over against; foremost; before; onward" (Mid.Pers. fra-; O.Pers. fra- "forward, forth;" Av. frā "forth," pouruua- "first"; cf. Skt. pūrva- "first," pra- "before, formerly;" Gk. pro; L. pro; O.E. fyrst "foremost," superlative of fore, E. fore) + zad past stem of zadan "to strike, beat, dash against; to shoot" ( Mid.Pers. zatan, žatan; O.Pers.; Av. jan-, gan- "to strike, hit, smite, kill" (jantar- "smiter"); cf. Skt. han- "to strike, beat" (hantar- "smiter, killer"); Gk. theinein "to strike," phonos "murder;" L. fendere "to strike, push;" Gmc. *gundjo "war, battle;" PIE *g^when- "to strike, kill").

To catch up with in traveling or pursuit; draw even with (Dictionary.com).

→ over-; → take.

Farâzrasidan, from farâz "upon, above, over," → height, + rasidan "to attain, to arrive," → access.

A note of lesser intensity and higher frequency than the fundamental note, and superimposed upon the latter to give a note of characteristic quality. Overtones whose frequencies are an integral multiple of the fundamental are said to form a harmonic series. The fundamental with a frequency f₁ is the first harmonic. The frequency 2f₁ is the first overtone and so on.

→ over-; → tone.

Voltage which exceeds the normal value between a conductor and earth.

→ over-; → voltage.

Any of an order (Strigiformes) of chiefly nocturnal birds of prey with a large head and eyes, short hooked bill, strong talons, and soft fluffy often brown-mottled plumage (Merriam-Webster.com).

Owl, from O.E. ule, from P.Gmc. *uwwalon (cf. Du. uil, O.H.G. uwila, Ger. Eule), a diminutive of root *uwwa, which is imitative of an owl's hoot (cf. L. ulula "owl;" Gk. ololyzein "to cry aloud," Skt. uluka- "owl."

Buf "owl;" Mid.Pers. bûf "owl," related to Av. bucahin- "he who is prone to howling," buxti- "howling, hissing" (Pokorny); cf. Skt. bukk- "to bark, yelp;" Gk. buas "owl;" L. bubo "owl" (Fr. hibou); Arm. bou "owl."
Joqd "owl," probably related to jiq "shreak, clamour, cry."

A → planetary nebula in the constellation → Ursa Major, one of the four planetary nebulae in → Messier catalog. It is one of the more complex planetary nebulae known. Its appearance has been interpreted as that of a cylindrical torus shell viewed obliquely, so that the projected matter-poor ends of the cylinder correspond with the Owl's eyes. Also known as M97 or NGC 3587.

Discovered by Pierre Méchain in 1781, the name goes back to Lord Rosse, who first used it in 1848. → owl; → nebula.

The substance which supplies the → oxygen in an → oxidation → reaction. Same as → oxydizing agent agent and → oxidizer.

Agent noun from → oxidize.

The combination of → oxygen with a substance, or the removal of → hydrogen from it.

Verbal noun of → oxidize.

The total number of electrons that an atom either gains or loses in order to form a chemical bond with another atom. In other words, the charge that atom would have if the compound was composed of ions. The oxidation number of an atom is zero in a neutral substance that contains atoms of only one element. Same as → oxidation state.

→ oxidation; → number.

Same as → oxidation number.

→ oxidation; → state.