takeoff booster vs takeoff rocket

takeoff booster and takeoff rocket both are nouns.

Word	Noun	Adjective	Verb	Adverb
takeoff booster	Yes	No	No	No
takeoff rocket	Yes	No	No	No

As nouns, takeoff booster and takeoff rocket are synonyms defined as:

takeoff booster and takeoff rocket: the first stage of a multistage rocket

Other synonyms of takeoff booster include booster, booster rocket, booster unit.

takeoff booster (noun)	takeoff rocket (noun)
the first stage of a multistage rocket	the first stage of a multistage rocket