windfall profit vs earnings

windfall profit and earnings both are nouns.

Word	Noun	Adjective	Verb	Adverb
windfall profit	Yes	No	No	No
earnings	Yes	No	No	No

As nouns, earnings is a hypernym of windfall profit; that is, earnings is a word with a broader meaning than windfall profit:

windfall profit: profit that occurs unexpectedly as a consequence of some event not controlled by those who profit from it
earnings: the excess of revenues over outlays in a given period of time (including depreciation and other non-cash expenses)

Other hypernyms of windfall profit include lucre, net, net income, net profit, profit, profits.

windfall profit (noun)	earnings (noun)
profit that occurs unexpectedly as a consequence of some event not controlled by those who profit from it	something that remunerates
	the excess of revenues over outlays in a given period of time (including depreciation and other non-cash expenses)