See <<booster engine>>, <<booster rocket>>, <<launch vehicle>>

A small generator inserted in series or parallel with a larger generator to maintain normal voltage output under heavy loads.

1. A separate radio-frequency amplifier connected between an antenna and a television receiver to amplify weak signals.

2. A radio-frequency amplifier that amplifies and rebroadcasts a received television or communication radio carrier frequency for reception by the general public.

The dose of an immunizing agent given to stimulate the effects of a previous dose of the same agent.

A compressor that is used as the first stage in a cascade refrigerating system.

An assembly of metal parts and explosive charge provided to augment the explosive component of a fuse, to cause detonation of the main explosive charge of the munition.