step rocket

Từ điển WordNet v3.1 - WordNet Dictionary

noun

a rocket having two or more rocket engines (each with its own fuel) that are fired in succession and jettisoned when the fuel is exhausted
• Syn:
multistage rocket
• Hypernyms:
rocket, projectile
• Part Meronyms:
booster, booster rocket, booster unit, takeoff booster, takeoff rocket