playing vs business

playing and business both are nouns.

Word	Noun	Adjective	Verb	Adverb
playing	Yes	No	No	No
business	Yes	No	No	No

As nouns, business is a hyponym of playing; that is, business is a word with a more specific, narrower meaning than playing:

playing (noun)	business (noun)
the action of taking part in a game or sport or other recreation	the principal activity in your life that you do to earn money
the act of playing a musical instrument	the activity of providing goods and services involving financial and commercial and industrial aspects
the performance of a part or role in a drama	the volume of commercial activity
	incidental activity performed by an actor for dramatic effect
	an immediate objective
	a rightful concern or responsibility
	a commercial or industrial enterprise and the people who constitute it
	customers collectively
	business concerns collectively