Lack, n.
Etymology: [OE. lak; cf. D. lak slander, laken to blame, OHG. lahan, AS. leán.]
1. Blame; cause of blame; fault; crime; offense. [Obs.] Chaucer.
2. Deficiency; want; need; destitution; failure; as, a lack of sufficient food. She swooneth now and now for lakke of blood. Chaucer. Let his lack of years be no impediment. Shak.
3 other Webster entries under this spelling
Lack, v. t. [imp. & p. p. Lacked; p. pr. & vb. n. Lacking.]
1. To blame; to find fault with. [Obs.] Love them and lakke them not. Piers Plowman.
2. To be without or destitute of; to want; to need. If any of you lack wisdom, let him ask of God. James i. 5.
Lack, v. i.
1. To be wanting; often, impersonally, with of, meaning, to be less than, short, not quite, etc. What hour now I think it lacks of twelve. Shak. Peradventure there shall lack five of the fifty. Gen. xvii. 28.
2. To be in want. The young lions do lack, and suffer hunger. Ps. xxxiv. 10.
Lack, interj.
Exclamation of regret or surprise. [Prov. Eng.] Cowper.
Shades of meaning
Fernald lists lack only as an antonym, under excess.
He lists it without comment; the entries above explain its neighbors.