Piper cubeba vs true pepper

Piper cubeba and true pepper both are nouns.

Word	Noun	Adjective	Verb	Adverb
Piper cubeba	Yes	No	No	No
true pepper	Yes	No	No	No

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

Piper cubeba: tropical southeast Asian shrubby vine bearing spicy berrylike fruits
true pepper: any of various shrubby vines of the genus Piper

Other hypernyms of Piper cubeba include pepper vine.

Piper cubeba (noun)	true pepper (noun)
tropical southeast Asian shrubby vine bearing spicy berrylike fruits	any of various shrubby vines of the genus Piper