cash flow vs income

cash flow and income both are nouns.

Word	Noun	Adjective	Verb	Adverb
cash flow	Yes	No	No	No
income	Yes	No	No	No

As nouns, income is a hypernym of cash flow; that is, income is a word with a broader meaning than cash flow:

cash flow: the excess of cash revenues over cash outlays in a given period of time (not including non-cash expenses)
income: the financial gain (earned or unearned) accruing over a given period of time

cash flow (noun)	income (noun)
the excess of cash revenues over cash outlays in a given period of time (not including non-cash expenses)	the financial gain (earned or unearned) accruing over a given period of time