deficiency

Noun

• lack of an adequate quantity or number
  • the inadequacy of unemployment benefits
    

• the state of needing something that is absent or unavailable
  • 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 words

• Synonyms: 
  insufficiency , inadequacy , lack , want
• Antonyms: 
  sufficiency , adequacy