An Etymological Dictionary of Astronomy and Astrophysics

The Greater Dog. A → constellation in the southern hemisphere which contains → Sirius, the brightest star of the whole sky. Approximate position: R.A. 7 h, Dec. -20°; abbreviation CMa; genitive form Canis Majoris.

Etymology (EN): L. Canis Major, from canis “dog” (cf. Gk. kuon, Skt. svâ-, Av. spâ-, Pers. sag; PIE *kwon-) + Maior “larger,” from L. major, irregular comp. of magnus “large, great” (cf. Gk. megas, Av. maz-, masan-, mazant- “great, important,” Skt. mah-, mahant-, Mod.Pers. meh; PIE *meg- “great”).
Canis Major is usually seen as one of the two hunting dogs of the hunter Orion. The other dog is Canis Minor, the Little Dog.

Etymology (PE): Sag-e Bozorg, from sag, see the above paragraph, + bozorg “large, great,” Mid.Pers. vuzurg, O.Pers. vazarka- “great,” Av. vazra- “club,” Skt. vajati, vaja- “strength,” vajra- “Indira’s thunderbolt,” L. vegere “to be lively,” PIE *weg- “to be strong, be lively.”