social function vs social affair

social function and social affair both are nouns.

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

As nouns, social function and social affair are synonyms defined as:

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

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

social function (noun)	social affair (noun)
a formal or official social gathering or ceremony of people	a formal or official social gathering or ceremony of people