An Etymological Dictionary of Astronomy and Astrophysics

1. The apparent force of → gravitation on an object at or near the surface of a star, planet, satellite, etc.
   

2. Same as → gravitation and → gravitational interaction.

Etymology (EN): From L. gravitatem (nom. gravitas) “weight, heaviness,” from gravis “heavy,” from PIE base *g^wrə- “heavy” (cf. Mod.Pers. gerân “heavy;” Av. gouru- “heavy;” Skt. guru- “heavy, weighty, venerable;” Gk. baros “weight,” barys “heavy;” Goth. kaurus “heavy”).

Etymology (PE): Gerâni, noun of gerân “heavy, ponderous, valuable,” from Mid.Pers. garân “heavy, hard, difficult;” Av. gouru- “heavy” (in compounds), from Proto-Iranian *garu-; cognate with gravity, as above.