undertaking vs task

undertaking and task both are nouns.

Word	Noun	Adjective	Verb	Adverb
undertaking	Yes	No	No	No
task	Yes	No	Yes	No

As nouns, undertaking and task are synonyms defined as:

Other synonyms of undertaking include labor, labour, project.

undertaking (noun)	task (noun)
any piece of work that is undertaken or attempted	a specific piece of work required to be done as a duty or for a specific fee
the trade of a funeral director	any piece of work that is undertaken or attempted

undertaking (verb)	task (verb)
	use to the limit
	assign a task to