Projectile
mid 17th century: modern Latin, from project- ‘thrown forth’, from the verb proicere (see project).
wiktionary
From Medieval Latin prōiectilis(“projectile”), from Latin prōiectus, perfect passive participle of prōiciō(“throw forth; extend; expel”).
etymonline
projectile (n.)
"body projected or impelled forward by force," 1660s, from Modern Latin projectilis, from Latin proiectus, past participle of proicere "stretch out, throw forth," from pro- "forward" (see pro-) + combining form of iacere (past participle iactus) "to throw" (from PIE root *ye- "to throw, impel"). Specifically "a missile intended to be shot from a cannon by explosion of gunpowder, etc."
projectile (adj.)
1690s, "caused by impulse;" 1715, "impelling, throwing;" see project (v.) + -ile. By 1865 as "capable of being thrust forward." Projectile vomiting is attested from 1985.
