The Collaborative International Dictionary of English v.0.48:

Unseason \Un*sea"son\, v. t. [1st pref. un- + season.]
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   1. To make unseasoned; to deprive of seasoning.
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   2. To strike unseasonably; to affect disagreeably or
      unfavorably. [Obs.]
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            Why do I send this rustic madrigal,
            That may thy tuneful ear unseason quite? --Spenser.
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