exclusion vs omission

exclusion and omission both are nouns.

Word	Noun	Adjective	Verb	Adverb
exclusion	Yes	No	No	No
omission	Yes	No	No	No

As nouns, omission is a hypernym of exclusion; that is, omission is a word with a broader meaning than exclusion:

exclusion (noun)	omission (noun)
the act of forcing out someone or something	a mistake resulting from neglect
a deliberate act of omission	neglecting to do something; leaving out or passing over something
the state of being excluded	any process whereby sounds or words are left out of spoken words or phrases
the state of being excommunicated	something that has been omitted