worrywart vs worrier

worrywart and worrier both are nouns.

Word	Noun	Adjective	Verb	Adverb
worrywart	Yes	No	No	No
worrier	Yes	No	No	No

As nouns, worrywart and worrier are synonyms defined as:

worrywart and worrier: thinks about unfortunate things that might happen

Other synonyms of worrywart include fuss-budget, fusspot.

worrywart (noun)	worrier (noun)
thinks about unfortunate things that might happen	thinks about unfortunate things that might happen