episode vs serial

episode and serial both are nouns.

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

episode (noun)	serial (noun)
film consisting of a succession of related shots that develop a given subject in a movie	a serialized set of programs
a part of a broadcast serial	a periodical that appears at scheduled times
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

episode (adjective)	serial (adjective)
	pertaining to or occurring in or producing a series
	pertaining to or composed in serial technique
	of or relating to the sequential performance of multiple operations
	in regular succession without gaps