affair vs function

affair and function both are nouns.

Word	Noun	Adjective	Verb	Adverb
affair	Yes	No	No	No
function	Yes	No	Yes	No

As nouns, affair and function are synonyms defined as:

affair and function: a formal or official social gathering or ceremony of people

Other synonyms of affair include occasion, social affair, social function, social gathering, social occasion.

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

affair (noun)	function (noun)
a vaguely specified concern	the actions and activities assigned to or required or expected of a person or group
a formal or official social gathering or ceremony of people	what something is used for
a usually secretive or illicit sexual relationship	a set sequence of steps, part of larger computer program
	a formal or official social gathering or ceremony of people
	a formal or official social gathering or ceremony
	(mathematics) a mathematical relation such that each element of a given set (the domain of the function) is associated with an element of another set (the range of the function)
	a relation such that one thing is dependent on another

affair (verb)	function (verb)
	perform duties attached to a particular office or place or function
	perform as expected when applied
	serve a purpose, role, or function