disregard vs omission

disregard and omission both are nouns.

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

As nouns, omission is a hyponym of disregard; that is, omission is a word with a more specific, narrower meaning than disregard:

disregard (noun)	omission (noun)
willful lack of care and attention	a mistake resulting from neglect
lack of attention and due care	neglecting to do something; leaving out or passing over something
	any process whereby sounds or words are left out of spoken words or phrases
	something that has been omitted

disregard (verb)	omission (verb)
give little or no attention to
bar from attention or consideration
refuse to acknowledge