The Collaborative International Dictionary of English v.0.48:

Pestilence \Pes"ti*lence\, n. [F. pestilence, L. pestilentia.
   See Pestilent.]
   1. Specifically, the disease known as the plague; hence, any
      contagious or infectious epidemic disease that is virulent
      and devastating.
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            The pestilence that walketh in darkness. --Ps. xci.
                                                  6.
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   2. Fig.: That which is pestilent, noxious, or pernicious to
      the moral character of great numbers.
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            I'll pour this pestilence into his ear. --Shak.
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   Pestilence weed (Bot.), the butterbur coltsfoot (Petasites
      vulgaris), so called because formerly considered a remedy
      for the plague. --Dr. Prior.
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