boos
ter
复数形式
boosters
1
助推器, 加速器
a rocket that gives a spacecraft or missile the extra power it needs to leave the Earth's atmosphere
2
加强针, 加强剂量
an additional dose of vaccine required periodically in order to increase, maintain, or renew the effects of a previous one
A booster is an extra dose of a vaccine given to strengthen the immune response after the first doses. Boosters are typically given after the first vaccination series to ensure long-term protection against certain diseases. They help strengthen the body's defense and provide added protection against infections that may decrease over time or need extra support.
3
放大器, 助推器
an amplifier for restoring the strength of a transmitted signal
4
6
7
刺激物, 放大器
something that enables a person or thing to improve or increase