The Collaborative International Dictionary of English v.0.48:

Augmentation \Aug`men*ta"tion\, n. [LL. augmentatio: cf. F.
   augmentation.]
   1. The act or process of augmenting, or making larger, by
      addition, expansion, or dilation; increase.
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   2. The state of being augmented; enlargement.
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   3. The thing added by way of enlargement.
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   4. (Her.) A additional charge to a coat of arms, given as a
      mark of honor. --Cussans.
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   5. (Med.) The stage of a disease in which the symptoms go on
      increasing. --Dunglison.
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   6. (Mus.) In counterpoint and fugue, a repetition of the
      subject in tones of twice the original length.
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   Augmentation court (Eng. Hist.), a court erected by Stat.
      27 Hen. VIII., to augment the revenues of the crown by the
      suppression of monasteries. It was long ago dissolved.
      --Encyc. Brit.
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   Syn: Increase; enlargement; growth; extension; accession;
        addition.
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