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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   deflate \de*flate"\, v. t. [Pref. de- down + L. flare, flatus to
      blow.]
      To reduce from an inflated condition; used literally and
      metaphorically; as, to deflate a tire; to deflate
      expectations.
      [1913 Webster +PJC]