noun (n)

• a mental state characterized by a pessimistic sense of inadequacy and a despondent lack of activity(noun.state)

  Antonym:
  elation
  

  source: wordnet30
• a long-term economic state characterized by unemployment and low prices and low levels of trade and investment(noun.state)

  Synonym:
  economic crisis, slump
  

  source: wordnet30
• a sunken or depressed geological formation(noun.object)

  Synonym:
  natural depression
  Antonym:
  elevation, natural elevation
  

  source: wordnet30
• sad feelings of gloom and inadequacy(noun.feeling)

  source: wordnet30
• a period during the 1930s when there was a worldwide economic depression and mass unemployment(noun.time)

  Synonym:
  great depression
  

  source: wordnet30
• an air mass of lower pressure; often brings precipitation(noun.state)

  Synonym:
  low
  

  source: wordnet30
• a state of depression and anhedonia so severe as to require clinical intervention(noun.state)

  Synonym:
  clinical depression, depressive disorder
  

  source: wordnet30
• a concavity in a surface produced by pressing(noun.shape)

  Synonym:
  impression, imprint
  

  source: wordnet30
• angular distance below the horizon (especially of a celestial object)(noun.linkdef)

  source: wordnet30
• pushing down(noun.act)

  Example:
  Depression of the space bar on the typewriter.
  

  source: wordnet30
• The act of depressing.(noun)

  source: webster1913