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

Another name for → inert gas.

M.E., from O.Fr. rere "sparse," from L. rarus "loose, wide apart, thin, infrequent;" &rar; gas.

Kamyâb "rare, difficult to find," from kam "little, few; deficient, wanting; scarce" (Mid.Pers. kam "little, small, few," O.Pers./Av. kamna- "small, few"); + yâb present stem of yâftanyâftan, yâbidan "to find, discover; to obtain, acquire" (Mid.Pers. ayâftan, ayâpênitan "to reach, attain;" Manichean Mid.Pers. 'y'b "to attain;" Parthian, Sogdian (+ *pati-) pty'b "to reach, obtain;" Av. ap- "to reach, overtake," apayeiti "achieved, reached;" Skt. âp- "to reach, gain," âpnoti "reaches, gains;" Gk. hapto, haptomai "to touch, cling to, adhere to;" L. apiscor "touch, reach;" PIE base *ap- "to take, reach").

A gas whose pressure is much less than a reference pressure.

Past participle of → rarefy; → gas.

Actual gas whose molecules do not necessarily possess the properties assigned to those of an → ideal gas.

→ real; → gas.

A large → asterism of four stars, approximately square in shape, in the northern sky. Three of the stars, → → Markab, → Scheat, and → Algenib, belong to the constellation → Pegasus. The fourth, → Alpheratz, was lost to Pegasus when the constellation boundaries were formalised, and now lies just within the borders of → Andromeda.

→ square; → Pegasus.

Chahârguš, → tetragon; → Pegasus.

A gas composed of ultrarelativistic particles.

→ ultrarelativistic; → gas.

Same as → gas constant.

→ universal; → gas; → constant.