episode vs occurrence

episode and occurrence both are nouns.

Word	Noun	Adjective	Verb	Adverb
episode	Yes	No	No	No
occurrence	Yes	No	No	No

As nouns, occurrence is a hypernym of episode; that is, occurrence is a word with a broader meaning than episode:

Other hypernyms of episode include happening, natural event, occurrent.

episode (noun)	occurrence (noun)
film consisting of a succession of related shots that develop a given subject in a movie	an event that happens
a part of a broadcast serial	an instance of something occurring
a brief section of a literary or dramatic work that forms part of a connected series
a happening that is distinctive in a series of related events