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

1) General: A small compartment or bounded area forming part of a whole.
2) Fluid mechanics: A body of fluid (air, liquid, or → plasma) in which the process of → convection proceeds.
3) Electricity: A device for producing electric current by chemical action.

From L. cella "small room, hut," related to L. celare "to hide, conceal," from PIE base *kel- "conceal" (cf. Skt. cala "hut, house," Gk. kalia "hut, nest," kalyptein "to cover").

Yâxté "small room, closet," etymology unknown.

A body of → fluid which transports energy through the → convection process.

→ convective; → cell.

Possessing outstanding quality or superior merit; remarkably good (Dictionary.com).

M.E., from O.Fr. excellent "outstanding," from L. excellentem (nominative excellens) "towering, prominent, superior," pr.p. of excellere "to surpass, be superior,"from → ex- "out from" + cellere "to rise high, tower," related to celsus "high, great," from PIE root *kel- "to be elevated; hill;" from which are derived L. collis "hill," columna "projecting object," culmen "top, summit," cellere "raise;" Gk. kolonos "hill," kolophon "summit;" Lithuanian kalnas "mountain," kalnelis "hill;" E. hill; Pers. dialects (Gilân) kol, kulâ "hill," (Dâmqân) kalut, kolut "successive soil hills, hill," (Tabari) keti "hill," (Jâsk) kit "hill."

Mid.Pers. pahrom "excellent," variant pahlom, ultimately from *parθama- "the highest, the most elevated," literally "Parthian," adj. from Parθa(va)-; cf. pahlavân "hero," another similar respect word related to Parthia (Nyberg 1974).

An electrolytic cell capable of producing electric energy by electrochemical reaction.

→ galvanism; → cell.

A → primary cell in which the anode is a rod of carbon and the cathode a zinc rod both immersed in an electrolyte of ammonia plus a depolarizer.

Named after the inventor Georges Leclanché (1839-1882), a French chemist, → cell.

A → cell in which the electrochemical action producing the current is not normally reversible. Such a cell cannot be recharged by an electric current. → secondary cell.

→ primary; → cell.

An electric cell that can be charged by passing a current through it in reverse direction to its discharge. Same as → accumulator. See also → primary cell.

→ secondary; → cell.

One of a number of large convective cells (about 15,000-30,000 km in diameter) in the solar photosphere, distributed fairly uniformly over the solar disk, that last longer than a day.

→ super-; → granulation; → cell.

In fluid dynamics, a theorem that relates the speed of fluid flowing out of an opening to the height of fluid above the opening: v = (2gh)^1/2, where v is the exit velocity of the water, h is the height of the water column, and g is the acceleration due to gravity (9.81 m/s²). It was later shown to be a particular case of → Bernoulli's theorem.

After the Italian scientist Evangelista Torricelli (1608-1647), who found this relationship in 1643.