trajectory (n.)
"path described by a body moving under the influence of given forces," 1690s, from Modern Latin trajectorium, from trajectorius "of or pertaining to throwing across," from Latin traiectus "thrown over or across," past participle of traicere "throw across, shoot across," from Latin trans- "across" (see trans-) + icere, combining form of iacere "to throw" (see jet (v.)). Middle French and Middle English had trajectorie as "end of a funnel," from Latin traiectorium.