lack vs absence

lack and absence both are nouns.

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

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

Other hyponyms of lack include dearth, famine, shortage, deficit, mineral deficiency, shortness, stringency, tightness.

lack (noun)	absence (noun)
the state of needing something that is absent or unavailable	failure to be present
	the state of being absent
	the occurrence of an abrupt, transient loss or impairment of consciousness (which is not subsequently remembered), sometimes with light twitching, fluttering eyelids, etc.; common in petit mal epilepsy
	the time interval during which something or somebody is away

lack (verb)	absence (verb)
be without
To be insufficiently prepared