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

Very cold in temperature.

From Latin frigidus "cold, chill, cool," from stem of frigere "be cold;" related to noun frigus "cold, coldness, frost," from PIE root *srig- "cold;" cf. Gk. rhigos "cold, frost."

Sajan "very cold," variants šaja,, sajâm, šajad, Oss. I. syjyn/syd, D. sujun/sud "to freeze," Yaghnobi ši-, Yazghulami šed/šiy- "to freeze," Shughni šitô , Sariqoli š(i)tu "cold, ice." Proto-Ir. *saiH-/siH- "to freeze." Skt. syā- "to freeze, coagulate, become rigid."

In → plasma physics, a → quantity that describes the → resistance of a → charged particle to change its direction of motion under the influence of a perpendicular → magnetic field. Rigidity is defined as: R = r_LBc = (pc)/(Ze), where r_L is the → Larmor radius, B is → magnetic induction, c is the → speed of light, p is the → momentum of the particle, Z is → atomic number, and e the → electron charge. Since pc has the dimensions of energy and e the dimensions of charge, rigidity has the dimensions of → volts (a 10 GeV proton has a rigidity of 10 GV). In → cosmic ray studies, the energies of cosmic rays are often quoted in terms of their rigidities, rather than their energies per nucleon.

→ magnetic; → rigidity.

Same as → shear modulus.

→ modulus; → rigidity.

1) General: Stiff or unyielding; inflexible, strict, severe.
2) Physics: → rigid body; → rigidity.

From L. rigidus "hard, stiff, rough," from rigere "to be stiff;" related to L. frigus "cold," Gk. rhigos "frost, cold."

Saxtpây, from saxt, → hard, + pây present stem of pâyidan "to stand firm, to be constant, steady, fixed;" Mid.Pers. pâyitan, pâtan, pây- "to protect; wait, stand," Sogdian p'y "to protect, watch over;" O.Pers./Av. pâ(y)- "to protect, keep" pâtar- "protector, watcher," cf. Skt. pâ- "to protect, keep," pâti "protects;" Gk. poimen "shepherd," poma "lid, cover;" L. pastor "shepherd," panis "bread;" PIE base *pa- "to protect, guard, pasture, feed."

Mechanics: A system of many particles whose positions relative to one another remain fixed.

→ rigid; → body.

1) The quality or state of being → rigid. See also → modulus of rigidity.
2) → magnetic rigidity.

→ rigid + → -ity.