president vs business executive

president and business executive both are nouns.

Word	Noun	Adjective	Verb	Adverb
president	Yes	No	No	No
business executive	Yes	No	No	No

As nouns, business executive is a hypernym of president; that is, business executive is a word with a broader meaning than president:

Other hypernyms of president include corporate executive.

president (noun)	business executive (noun)
the chief executive of a republic	an executive in a business corporation
an executive officer of a firm or corporation
the head administrative officer of a college or university
the officer who presides at the meetings of an organization