An Etymological Dictionary of Astronomy and Astrophysics

An astronomical observation carried out using a telescope on Earth, as opposed to that from an orbiting satellite.

Etymology (EN): → ground; based, adj. of base, from
O.Fr. bas, from L. basis “foundation,” from Gk. basis “step, pedestal,” from bainein “to step;” → observation.

Etymology (PE): Nepâheš, → observation; az “from,” → ex-; zamin, → ground.