The Collaborative International Dictionary of English v.0.48:

Embase \Em*base"\, v. t. [Pref. em- + base, a. or v. t.: cf. OF.
   embaissier.]
   To bring down or lower, as in position, value, etc.; to
   debase; to degrade; to deteriorate. [Obs.]
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         Embased the valleys, and embossed the hills.
                                                  --Sylvester.
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         Alloy in coin of gold . . . may make the metal work the
         better, but it embaseth it.              --Bacon.
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         Such pitiful embellishments of speech as serve for
         nothing but to embase divinity.          --South.
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