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

1) General: The act of dragging or the state of being dragged.
2) Fluid mechanics: The → force that opposes the relative motion of an object through a → fluid. In → aeronautics, the component of aerodynamic force parallel to the relative wind tending to reduce the forward motion of the airplane. See also → lift; → thrust.
3) To pull or be pulled with force, especially along the ground or other surface.

From O.N. draga, O.E. dragan "to draw," from P.Gmc. *dragan "to draw, pull," from PIE base *dhragh- "to draw, drag on the ground" (cf. Skt. dhrajati "pulls, slides in," L. trahere "to pull," Rus. drogi "wagon."

Kerr, kerré, kerridan "drag," cf. Laki keronen, Hamadâni kerândan "to pull along, drag," Tâleši kernye, Tabari kərəš "to drag;" Lori, Hamadâni kerr "line, scratch;" related to Mid/Mod.Pers. kešidan, kašidan "to draw, protract, trail, drag, carry;" kâštan, keštan, kâridan "to cultivate, to plant, to make furrows;" Av. kar- "to strew seed, cultivate," kāraiieiti "cultivates," karš- "to draw (a furrow), till, plant;" cf. Skt. kar- "to scatter, strew, pour out," kars-, kársati "to pull, drag, plow;" Gk. pelo, pelomai "to move, to bustle;" PIE base k^wels- "to plow."
Vârâné, from vâ-, opposition prefix, → de-, + râné, from rândan "to push, drive, cause to go" (causative of raftan "to go, walk, proceed," present tense stem row-, Mid.Pers. raftan, raw-, Proto-Iranian *rab/f- "to go; to attack").

A hypothesis put forward to explain the null measurement of the → ether drift. According to this hypothesis, the Earth somehow drags the ether with it as our planet rotates on its axis and revolves around the Sun. However, the ether drag hypothesis contradicts results from several experiments, including the → aberration of starlight.

→ ether; → drag.

The alteration in the → free fall motion of a test → mass in the presence of a massive → rotating object, as compared to the identical case of a non-rotating object. This dragging of → inertial frames is predicted by → general relativity. Also called → Lense-Thirring effect.

→ frame; → drag.

A loss of → orbital angular momentum by tiny ring particles associated with their absorption and re-emission of → solar radiation. Also known as the → Poynting-Robertson effect (Ellis et al., 2007, Planetary Ring Systems, Springer).

→ Poynting-Robertson; → drag.