An Etymological Dictionary of Astronomy and Astrophysics

The most important function of an astronomical telescope, which is
directly related to the area (or to the square of the diameter) of the main mirror or lens.

Etymology (EN): → light; gathering, from O.E. gadrian, gædrian “to gather, collect;” → power.

Etymology (PE): Tavân, → power; gerdâvari, verbal noun of gerd âvardan, from gerd “round; around” (Mid.Pers. girt “round, all around,” O.Iranian *gart- “to twist, to wreathe,” cf. Skt. krt “to twist threads, spin, to wind, to surround,” kata- “a twist of straw;” Pali kata- “ring, bracelet;” Gk. kartalos “a kind of basket,” kyrtos “curved”) + âvardan “to bring,” Mid.Pers. âwurtan, âvaritan;
Av. ābar- “to bring, to possess,” from prefix ā- +
Av./O.Pers. bar- “to bear, carry,” bareθre “to bear (infinitive),” bareθri “a female that bears (children), a mother;” Mod.Pers. bordan “to carry;” Skt. bharati “he carries;” Gk. pherein; L. fero “to carry;” nur,
→ light.