booster

A booster is something that increases or enhances the strength, power, effectiveness, or range of something else. The term is used across fields to denote devices, substances, or systems designed to provide an additional boost rather than to replace the underlying function.

In medicine, a booster shot or booster dose is an additional vaccination given after the primary series to reinforce or extend immunity. Boosters are common for diseases with waning protection, and schedules vary by country and vaccine.

In aerospace and rocketry, a booster refers to an auxiliary rocket or stage that provides extra thrust to launch a payload and is often discarded after burnout. It can dramatically increase velocity and payload capacity.

In transportation safety, a booster seat is an infant/child seat that elevates a child so that seat belts fit properly. It is distinct from a child car seat and is used for a specific height/weight range.

In electronics and communications, a booster or booster amplifier increases signal strength, extending range in radios, cell networks, or fiber-optic links. A booster may be passive or active.

In utilities, a booster pump or booster station raises water pressure in plumbing, irrigation, or industrial processes.

In social organizations, a booster club or booster organization supports sports teams or events, often through fundraising and volunteer activities.