speller vs poor speller

speller and poor speller both are nouns.

Word	Noun	Adjective	Verb	Adverb
speller	Yes	No	No	No
poor speller	Yes	No	No	No

As nouns, speller and poor speller are synonyms defined as:

Other synonyms of speller include good speller.

speller (noun)	poor speller (noun)
an introductory textbook to teach spelling	someone who spells words
someone who spells words