Antonym of accelerate

Antonyms of verb accelerate

2 senses of accelerate

Sense 1:

accelerate, speed up, speed, quicken
Antonym of decelerate (Sense 1)
=>decelerate, slow, slow down, slow up, retard

Sense 2:

accelerate, speed, speed up
Antonym of decelerate (Sense 2)
=>decelerate, slow down