extra vs redundant

extra is a noun but redundant is not a noun.

Word	Noun	Adjective	Verb	Adverb
extra	Yes	Yes	No	Yes
redundant	No	Yes	No	No

As adjectives, extra and redundant are synonyms defined as:

Other synonyms of extra include excess, spare, supererogatory, superfluous, supernumerary, surplus.

extra (noun)	redundant (noun)
something additional of the same kind
an additional edition of a newspaper (usually to report a crisis)
a minor actor in crowd scenes

extra (adjective)	redundant (adjective)
further or added	more than is needed, desired, or required
more than is needed, desired, or required	repetition of same and identical sense with different and non-identical words
added to a regular schedule

extra (adverb)	redundant (adverb)
unusually or exceptionally