income tax bracket vs income bracket

income tax bracket and income bracket both are nouns.

Word	Noun	Adjective	Verb	Adverb
income tax bracket	Yes	No	No	No
income bracket	Yes	No	No	No

As nouns, income tax bracket and income bracket are synonyms defined as:

income tax bracket and income bracket: a category of taxpayers based on the amount of their income

Other synonyms of income tax bracket include tax bracket.

income tax bracket (noun)	income bracket (noun)
a category of taxpayers based on the amount of their income	a category of taxpayers based on the amount of their income