by-product vs result

by-product and result both are nouns.

Word	Noun	Adjective	Verb	Adverb
by-product	Yes	No	No	No
result	Yes	No	Yes	No

As nouns, result is a hypernym of by-product; that is, result is a word with a broader meaning than by-product:

Other hypernyms of by-product include consequence, effect, event, issue, outcome, upshot.

by-product (noun)	result (noun)
a product made during the manufacture of something else	a statement that solves a problem or explains how to solve the problem
a secondary and sometimes unexpected consequence	the semantic role of the noun phrase whose referent exists only by virtue of the activity denoted by the verb in the clause
	something that results
	a phenomenon that follows and is caused by some previous phenomenon

by-product (verb)	result (verb)
	come about or follow as a consequence
	issue or terminate (in a specified way, state, etc.); end
	produce as a result or residue