deficiency
1. [ noun ] the state of needing something that is absent or unavailable
Synonyms: lack want
Examples:

"there is a serious lack of insight into the problem" "water is the critical deficiency in desert regions" "for want of a nail the shoe was lost"

Related terms: need absence dearth stringency sideropenia mineral_deficiency want
2. [ noun ] lack of an adequate quantity or number
Synonyms: inadequacy insufficiency
Examples:

"the inadequacy of unemployment benefits"

Related terms: sufficiency sufficiency amount deficit scarcity meagerness
Similar spelling:   deficient
  devising