cayenne vs chilli pepper

cayenne and chilli pepper both are nouns.

Word	Noun	Adjective	Verb	Adverb
cayenne	Yes	No	No	No
chilli pepper	Yes	No	No	No

As nouns, cayenne and chilli pepper are synonyms defined as:

cayenne and chilli pepper: plant bearing very hot and finely tapering long peppers; usually red

Other synonyms of cayenne include Capsicum annuum longum, cayenne pepper, chili pepper, jalapeno, long pepper.

cayenne (noun)	chilli pepper (noun)
ground pods and seeds of pungent red peppers of the genus Capsicum	plant bearing very hot and finely tapering long peppers; usually red
a long and often twisted hot red pepper
plant bearing very hot and finely tapering long peppers; usually red