booster vs admirer

booster and admirer both are nouns.

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

As nouns, booster and admirer are synonyms defined as:

Other synonyms of booster include champion, friend, protagonist, supporter.

booster (noun)	admirer (noun)
an additional dose that makes sure the first dose was effective	someone who admires a young woman
the first stage of a multistage rocket	a person who backs a politician or a team etc.
an amplifier for restoring the strength of a transmitted signal	a person who admires; someone who esteems or respects or approves
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.