augmenter

or aug·men·tor

[ awg-men-ter ]
/ ɔgˈmɛn tər /

noun

a person or thing that augments.
Aviation, Rocketry. any auxiliary device, as an afterburner, for additional thrust from the exhaust of a jet or rocket engine.

Origin of augmenter

First recorded in 1525–35; augment + -er1, -or2