box office vs receipts

box office and receipts both are nouns.

Word	Noun	Adjective	Verb	Adverb
box office	Yes	No	No	No
receipts	Yes	No	No	No

As nouns, receipts is a hypernym of box office; that is, receipts is a word with a broader meaning than box office:

Other hypernyms of box office include gross, revenue.

box office (noun)	receipts (noun)
the office where tickets of admission are sold	the entire amount of income before any deductions are made
total admission receipts for an entertainment