parabola n.

"allegorical or metaphorical narrative, usually having a moral for instruction," late 13c., parabol, modern form from early 14c., "saying or story in which something is expressed in terms of something else," from Old French parable "parable, parabolic style in writing" (13c.), from Latin parabola "comparison," from Greek parabolē "a comparison, parable," literally "a throwing beside," hence "a juxtaposition," from para- "alongside" (see para- (1)) + bolē "a throwing, casting, beam, ray," related to ballein "to throw" (from PIE root *gwele- "to throw, reach").

Rendered in Old English as bispell. In Vulgar Latin, parabola took on the meaning "word," hence Italian parlare, French parler "to speak" (see parley (n.)).

*gwelə-, also *gwel-, Proto-Indo-European root meaning "to throw, reach," with extended sense "to pierce."

It forms all or part of: anabolic; arbalest; astrobleme; ball (n.2) "dancing party;" ballad; ballet; ballista; ballistic; ballistics; belemnite; catabolism; devil; diabolical; discobolus; emblem; embolism; hyperbola; hyperbole; kill (v.); metabolism; palaver; parable; parabola; parley; parliament; parlor; parol; parole; problem; quell; quail (v.) "lose heart, shrink, cower;" symbol.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit apa-gurya "swinging," balbaliti "whirls, twirls;" Greek ballein "to throw, to throw so as to hit," also in a looser sense, "to put, place, lay," bole "a throw, beam, ray," belemnon "dart, javelin," belone "needle," ballizein "to dance;" Armenian kelem "I torture;" Old Church Slavonic zali "pain;" Lithuanian galas "end," gėla "agony," gelti "to sting."

mid-15c., parabolik, "figurative, allegorical, of or pertaining to a parable or a parabole," from Medieval Latin parabolicus, from late Greek parabolikos "figurative," from parabolē "comparison" (see parable). In geometry, "of or pertaining to a parabola," by 1702 (see parabola). Related: Parabolical.