Lack (noun)
A defect or failing; moral or spiritual degeneracy.
Lack (noun)
A deficiency or need (of something desirable or necessary); an absence, want.
Lack (verb)
To be without, to need, to require.
“My life lacks excitement.”
Lack (verb)
To be short (of or for something).
“He’ll never lack for company while he’s got all that money.”
Lack (verb)
To be in want.
Lack (verb)
To see the deficiency in (someone or something); to find fault with, to malign, reproach.
Lacking (noun)
The absence of something; a lack.
Lacking (adjective)
Missing or not having enough of (a good quality, etc).
“This cheese is lacking in pungency.”
Wiktionary