An Etymological Dictionary of Astronomy and Astrophysics

An important astronautical technique whereby a spacecraft takes up a tiny fraction of the gravitational energy of a planet it is flying by, allowing it to change trajectory and speed. Also known as → gravitational slingshot or → gravitational assist.

Etymology (EN): Slingshot, from sling, from M.E. slyngen, from O.N. slyngva “to sling, fling” + shot, from M.E., from O.E. sc(e)ot, (ge)sceot; cf. Ger. Schoss, Geschoss; → effect.

Etymology (PE): Oskar, → effect; falâxan “sling;” from Av. fradaxšana- “sling,” fradaxšanya- “sling, sling-stone;”