common pepper vs true pepper

common pepper and true pepper both are nouns.

Word	Noun	Adjective	Verb	Adverb
common pepper	Yes	No	No	No
true pepper	Yes	No	No	No

As nouns, true pepper is a hypernym of common pepper; that is, true pepper is a word with a broader meaning than common pepper:

common pepper: climber having dark red berries (peppercorns) when fully ripe; southern India and Sri Lanka; naturalized in northern Burma and Assam
true pepper: any of various shrubby vines of the genus Piper

Other hypernyms of common pepper include pepper vine.

common pepper (noun)	true pepper (noun)
climber having dark red berries (peppercorns) when fully ripe; southern India and Sri Lanka; naturalized in northern Burma and Assam	any of various shrubby vines of the genus Piper