An Etymological Dictionary of Astronomy and Astrophysics

In its simple form, a device consisting of a body suspended from a fixed point on the end of a string to move to and fro by the action of gravity and acquired momentum. The period of oscillation for small amplitudes of swing is determined by the formula T = 2π √(l/g).

Etymology (EN): From Mod.L. pendulum, noun use of neuter of L. pendulus “hanging down,” from pendere “to hang.”

Etymology (PE): Âvang, related to âvixtan, âviz- “to hang” (akin to bixtan, biz- “to shake, to sort out, to sift”); Mid.Pers. âwixtan “to hang” (Sogdian wyc “to move, shake;” Chorasmian wc- “to tremble, shake;” Ossetic wigyn “to shake,” awynzyn “to hang”), from prefixed (â-) Proto-Iranian base *uij-, *uic- “to shake, swing;” cf. Av. vij- “to shake, swing,” vaējant- “swinging;” cf. Skt. vej- “to tremble, wince.”