An Etymological Dictionary of Astronomy and Astrophysics

1. A measure of the → amplification of an electronic device, usually expressed as the ratio of → output power to → input power.
   
2. → antenna gain.

Etymology (EN): From M.Fr. gain, from O.Fr. gaaigne, from guaaignier “to obtain,” from Germanic *waidanjan “to hunt, plunder,” also “to graze, pasture,” from P.Gmc. *wartho “hunting ground” (cf. Ger. weide “pasture, pasturage”); PIE base *weiə- “to go after something, strive after.”

Etymology (PE): Bahré, from bahr “part, portion, share, lot;” Av. baxəδra- “portion,” from bag- “to attribute, allot,” → division.