no-brainer vs task

no-brainer and task both are nouns.

Word	Noun	Adjective	Verb	Adverb
no-brainer	Yes	No	No	No
task	Yes	No	Yes	No

As nouns, task is a hypernym of no-brainer; that is, task is a word with a broader meaning than no-brainer:

Other hypernyms of no-brainer include labor, labour, project, undertaking.

no-brainer (noun)	task (noun)
anything that requires little thought	a specific piece of work required to be done as a duty or for a specific fee
	any piece of work that is undertaken or attempted

no-brainer (verb)	task (verb)
	use to the limit
	assign a task to