1.Definition: (chemistry) a substance that initiates or accelerates a chemical reaction without itself being affected

Related Noun(s):catalyst

Category: General

2.Definition: a pedal that controls the throttle valve

Related Noun(s):gas, gun, throttle

Category: Objects

3.Definition: a scientific instrument that increases the kinetic energy of charged particles

Category: Objects

4.Definition: a valve that regulates the supply of fuel to the engine

Related Noun(s):throttle

Category: Objects