meeting vs social occasion

meeting and social occasion both are nouns.

Word	Noun	Adjective	Verb	Adverb
meeting	Yes	No	No	No
social occasion	Yes	No	No	No

As nouns, social occasion is a hypernym of meeting; that is, social occasion is a word with a broader meaning than meeting:

meeting: a small informal social gathering
social occasion: a formal or official social gathering or ceremony of people

Other hypernyms of meeting include affair, function, occasion, social affair, social function, social gathering.

meeting (noun)	social occasion (noun)
the social act of assembling for some common purpose	a formal or official social gathering or ceremony of people
the act of joining together as one
a casual or unexpected convergence
a formally arranged gathering
a small informal social gathering
a place where things merge or flow together (especially rivers)