lack vs need

lack and need both are nouns.

Word	Noun	Adjective	Verb	Adverb
lack	Yes	No	Yes	No
need	Yes	No	Yes	No

As nouns, need is a hypernym of lack; that is, need is a word with a broader meaning than lack:

Other hypernyms of lack include demand.

lack (noun)	need (noun)
the state of needing something that is absent or unavailable	the psychological feature that arouses an organism to action toward a desired goal; the reason for the action; that which gives purpose and direction to behavior
	anything that is necessary but lacking
	a condition requiring relief
	a state of extreme poverty or destitution

lack (verb)	need (verb)
be without	have need of
To be insufficiently prepared	have or feel a need for
	require as useful, just, or proper