underdrive
verbEtymology From under- + drive.
1
To slow the rate of rotation in (a pulley-based system).
underdrive
adjEtymology From under- + drive.
1
Designed to turn at a slower speed than stock.
Of a crankshaft or accessory pulley
Entry derived from the Wiktionary, under licence CC BY-SA 4.0 — list of authors.