slow down vs decelerate

slow down and decelerate both are verbs.

Word	Noun	Adjective	Verb	Adverb
slow down	No	No	Yes	No
decelerate	No	No	Yes	No

As verbs, slow down and decelerate are synonyms defined as:

Other synonyms of slow down include retard, slow, slow up.

As verbs, slow down and decelerate are synonyms defined as:

As verbs, decelerate is a hypernym of slow down; that is, decelerate is a word with a broader meaning than slow down:

Other hypernyms of slow down include retard, slow, slow down, slow up.

slow down (verb)	decelerate (verb)
become less tense, rest, or take one's ease	lose velocity; move more slowly
lose velocity; move more slowly	reduce the speed of
become slow or slower
reduce the speed of
cause to proceed more slowly