WordNet sense 1 (erect European annual often grown as a salad crop to be harvested when young and tender):

arugula, roquette, Eruca sativa, Eruca vesicaria sativa, garden rocket, rocket salad

WordNet sense 2 (propels bright light high in the sky, or used to propel a lifesaving line or harpoon):

skyrocket

WordNet sense 3 (any vehicle self-propelled by a rocket engine):

projectile

WordNet sense 4 (a jet engine containing its own propellant and driven by reaction propulsion):

rocket engine