pepper vs black pepper

pepper and black pepper both are nouns.

Word	Noun	Adjective	Verb	Adverb
pepper	Yes	No	Yes	No
black pepper	Yes	No	No	No

As nouns, black pepper is a hyponym of pepper; that is, black pepper is a word with a more specific, narrower meaning than pepper:

pepper: pungent seasoning from the berry of the common pepper plant of East India; use whole or ground
black pepper: pepper that is ground from whole peppercorns with husks on

Other hyponyms of pepper include white pepper.

As nouns, pepper and black pepper are synonyms defined as:

pepper and black pepper: climber having dark red berries (peppercorns) when fully ripe; southern India and Sri Lanka; naturalized in northern Burma and Assam

Other synonyms of pepper include common pepper, Madagascar pepper, Piper nigrum, white pepper.

pepper (noun)	black pepper (noun)
pungent seasoning from the berry of the common pepper plant of East India; use whole or ground	pepper that is ground from whole peppercorns with husks on
sweet and hot varieties of fruits of plants of the genus Capsicum	climber having dark red berries (peppercorns) when fully ripe; southern India and Sri Lanka; naturalized in northern Burma and Assam
any of various tropical plants of the genus Capsicum bearing peppers
climber having dark red berries (peppercorns) when fully ripe; southern India and Sri Lanka; naturalized in northern Burma and Assam

pepper (verb)	black pepper (verb)
attack and bombard with or as if with missiles
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