chilli pepper vs long pepper

chilli pepper and long pepper both are nouns.

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

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

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

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

chilli pepper (noun)	long pepper (noun)
plant bearing very hot and finely tapering long peppers; usually red	plant bearing very hot and finely tapering long peppers; usually red
	slender tropical climber of the eastern Himalayas