nib vs pen nib

nib and pen nib both are nouns.

Word	Noun	Adjective	Verb	Adverb
nib	Yes	No	No	No
pen nib	Yes	No	No	No

As nouns, nib and pen nib are synonyms defined as:

nib (noun)	pen nib (noun)
horny projecting mouth of a bird	the writing point of a pen
the writing point of a pen