The smaller and outermost of Mars' two satellites. It measures 12.6 km in size, and orbits Mars every 30.2 hours at a distance of about 23,500 km. It was discovered by the American astronomer Asaph Hall in 1877.
In Gk. mythology, Deimos, meaning "fear, terror," is one of the sons of Ares (Mars) and Aphrodite (Venus).
Chemistry: A process in which all charged species are removed from
dâdâr-bâvari (#), izad-bâvari
1) Belief in the existence of a → God on the evidence of
→ reason and → nature only,
with rejection of supernatural revelation (distinguished from
dâdâr-bâvar (#), izad-bâvar
A person who believes in → deism.
1) izad (#); 2) izadgân
Fr.: 1) dieu, déesse; 2) divinité
1) A god or goddess.
M.E. deite, from O.Fr., from L.L. deitat- (nominative deitas), from L. dei- (combining form of deus "god") + -tat- "-ty," formed after L. divinitas "divinity."
Izad "god;" from Mid.Pers. yazêt "god; angel," izišn "performance of the religious rites, worship," yašt "worship, religious ceremony," yaštan "to venerate, to perform the religious ceremony;" O.Pers. yad- "to worship;" Av. yaz- "to sacrifice, worship, venerate," yazata- "deities," yasna- "religious rite" (Mod.Pers. jašn "feast"); Proto-Ir. *iaz- "to sacrifice, worship, venerate."
Fr.: opérateur del
In → vector calculus,
a vector → partial derivative represented by the symbol
→ nabla and defined in three dimensions to be:
From Gk. alphabet letter delta.
The amount of time by which an event is retarded.
From O.Fr. délaier, from dé-→ de- "away, from" + laiier, from laiss(i)er "to leave," from L. laxare "to loosen, release, set free."
Derang, from Mid.Pers. dirang, drang "delay, lateness; long, lasting," Av. drənj- "to fix, fasten, hold," Proto-Iranian *dra(n)j- "to fix, fasten, hold."
Fr.: temps de retard, délai
Same as → delay.
Fr.: neutrons retardés
Neutrons resulting from nuclear fission which are emitted with a measurable time delay. Delayed neutrons are responsible for the ability to control the rate at which power can rise in a reactor. → prompt neutrons.
delayed supernova explosion
oskaft-e bâderang-e abar-now-axtar
Fr.: explosion retardée de supernova
A mechanism predicted by theoretical models of → supernova explosion that operates after the → supernova shock fails to deliver a → prompt supernova explosion. The delayed supernova explosion mechanism assumes that a few tenth of a second after the → iron core collapse, the supernova shock is stalled due to energy dissipation. The material between the → protoneutron star and the stalled shock is mainly disintegrated into neutrons and protons due to the high temperatures (a few MeV) in this region. As the → neutrinos coming from the protoneutron star run through this material, a fraction of the neutrinos are captured by the → nucleons, and their energy is deposited in the material. As a result, the material behind the shock is heated by the neutrinos. If this neutrino heating is efficient enough, the stalled shock can be reinvigorated to bring about a supernova explosion.
Fr.: barrer, rayer
To strike out or remove (something written or printed); cancel; erase.
L. deletus, p.p. of delere "destroy, blot out, efface," from delevi, fro delinere "to erase by smudging," from → de- "from, away" + linere "to smear, wipe."
Rušidan, from Kurd. rušê "to be wiped off through rubbing;" cf. Av. fra.uruxti- "destruction;" Wakhi riz-, rəz-/rəzd- "to tear apart, rip up a seam;" Yaghnobi ruc/ructa, rušta "to shave off the skin, skin off;" Proto-Ir. *rauj- "to break, bust" (Cheung 2007).
1) An act or instance of deleting. The state of being deleted. A deleted word, passage, etc.
Verbal noun from → delete.
1) Fine in texture, quality, construction, etc.
M.E. delicat, from L. delicatus "alluring, delightful, dainty," of uncertain origin.
Dârmé, from Mid.Pers. dârmag "delicate;" cf. (dialect of Ferdows) dermi "fine thread," Sogd. žâm, žam "delicate."
L. delphinus, from Gk. delphin-, delphis; akin to Gk. delphys womb, cf. Skt. garbha- "womb; interior."
Dolfin loanword from Gk.
1) The fourth letter of the Greek alphabet (δ, Δ).
M.E. deltha, from L. delta, from Gk. delta; from the Phoenician name of the corresponding letter daleth "tent door."
Fr.: Delta Cephée
The prototype of classical → Cepheid variables, which is a pulsating → yellow supergiant. John Goodricke was the first in 1784 to discover its variability. The star shows a quick and sharp rise from minimum to maximum, and slowly declines to its minimum again. The changes in brightness are accompanied by and principally caused by changes in stellar temperature and also by changes in radius. δ Cephei was actually the second Cepheid variable to be discovered. The first one, Eta Aquilae, had been discovered earlier the same year by Edward Pigott. δ Cephei varies with a period of 5.366341 days (or 5 days 8 hours 37.5 minutes) from magnitude 3.48, spectral type F5 Ib in its maximum to magnitude 4.37, spectral type G2 Ib in its minimum. It lies at a distance of 1,340 → light-years.
râne-ye deltâ , ~ vâkil
Fr.: entraînement en déclinaison
Fr.: fonction delta
Same as → Dirac function.
Fr.: offset en déclinaison
Fr.: delta Orionis
Same as → Mintaka.