president vs chairwoman

president and chairwoman both are nouns.

Word	Noun	Adjective	Verb	Adverb
president	Yes	No	No	No
chairwoman	Yes	No	No	No

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

president: the officer who presides at the meetings of an organization
chairwoman: the female officer who presides at the meetings of an organization

Other hyponyms of president include Kalon Tripa, vice chairman, chairman.

president (noun)	chairwoman (noun)
the chief executive of a republic	the female officer who presides at the meetings of an organization
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