The Collaborative International Dictionary of English v.0.48:

Abbreviate \Ab*bre"vi*ate\ ([a^]b*br[=e]"v[i^]*[=a]t), v. t.
   [imp. & p. p. Abbreviated; p. pr. & vb. n. Abbreviating.]
   [L. abbreviatus, p. p. of abbreviare; ad + breviare to
   shorten, fr. brevis short. See Abridge.]
   1. To make briefer; to shorten; to abridge; to reduce by
      contraction or omission, especially of words written or
      spoken.
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            It is one thing to abbreviate by contracting,
            another by cutting off.               --Bacon.
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   2. (Math.) To reduce to lower terms, as a fraction.
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