knock vs rap

knock and rap both are nouns.

Word	Noun	Adjective	Verb	Adverb
knock	Yes	No	Yes	No
rap	Yes	No	Yes	No

As nouns, knock and rap are synonyms defined as:

Other synonyms of knock include belt, whack, whang.

As verbs, rap is a hypernym of knock; that is, rap is a word with a broader meaning than knock:

Other hypernyms of knock include knap.

As verbs, knock and rap are synonyms defined as:

Other synonyms of knock include pink, tap.

knock (noun)	rap (noun)
the act of hitting vigorously	the act of hitting vigorously
negative criticism	a reproach for some lapse or misdeed
a vigorous blow	voluble conversation
the sound of knocking (as on a door or in an engine or bearing)	genre of African-American music of the 1980s and 1990s in which rhyming lyrics are chanted to a musical accompaniment; several forms of rap have emerged
a bad experience	the sound made by a gentle blow
	a gentle blow

knock (verb)	rap (verb)
find fault with; express criticism of; point out real or perceived flaws	talk volubly
knock against with force or violence	strike sharply
rap with the knuckles	perform rap music
deliver a sharp blow or push	make light, repeated taps on a surface
make light, repeated taps on a surface
sound like a car engine that is firing too early