booster dose vs recall dose

booster dose and recall dose both are nouns.

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

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

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

Other synonyms of booster dose include booster, booster shot.

booster dose (noun)	recall dose (noun)
an additional dose that makes sure the first dose was effective	an additional dose that makes sure the first dose was effective