booster vs booster dose

booster and booster dose both are nouns.

Word	Noun	Adjective	Verb	Adverb
booster	Yes	No	No	No
booster dose	Yes	No	No	No

As nouns, booster and booster dose are synonyms defined as:

booster and booster dose: an additional dose that makes sure the first dose was effective

Other synonyms of booster include booster shot, recall dose.

booster (noun)	booster dose (noun)
an additional dose that makes sure the first dose was effective	an additional dose that makes sure the first dose was effective
the first stage of a multistage rocket
an amplifier for restoring the strength of a transmitted signal
a thief who steals goods that are in a store
someone who is an active supporter and advocate
a person who backs a politician or a team etc.