Definitions
an additional dose that makes sure the first dose was effective
Word origin
From boost + -er.
Used in a sentence
“Nor is his district quite the Democratic bastion boosters describe: voters there narrowly backed Barack Obama in 2008, but voted for Mr Bush by a hefty margin in 2004.”
“When did you get your last tetanus booster?”
“In the September vaccine monitor survey from the Kaiser Family Foundation, 71 percent of unvaccinated respondents said the need for boosters indicated that the vaccines were not working.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer2 curated clues
01“Helper rocket”7 letters
02“Extra vaccine dose”7 letters
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