disregard vs dismiss

disregard is a noun but dismiss is not a noun.

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

As verbs, disregard and dismiss are synonyms defined as:

Other synonyms of disregard include brush aside, brush off, discount, ignore, push aside.

disregard (noun)	dismiss (noun)
willful lack of care and attention
lack of attention and due care

disregard (verb)	dismiss (verb)
give little or no attention to	declare void
bar from attention or consideration	bar from attention or consideration
refuse to acknowledge	end one's encounter with somebody by causing or permitting the person to leave
	cease to consider; put out of judicial consideration
	terminate the employment of; discharge from an office or position
	stop associating with