1690s, "to sprout or spurt forth, shoot out," from French jeter "to throw, thrust," from Late Latin iectare (abstracted from deiectare, proiectare, etc.), in place of Latin iactare "to toss about," frequentative of iacere "to throw, cast," from PIE root *ye- "to throw, impel."
Middle English had a verb getten, jetten meaning "to prance, strut, swagger, be showy" (c. 1400), from getter, jetter, the Old French form of the verb. Related: Jetted; jetting.
<a href="https://www.etymonline.com/word/ramjet">Etymology of ramjet by etymonline</a>
Harper, D. (n.d.). Etymology of ramjet. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/ramjet