The Collaborative International Dictionary of English v.0.48:

Carucage \Car"u*cage\, n. [LL. carrucagium (OF. charuage.), fr.
   LL. carruca plow, fr. L. carruca coach.]
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   1. (Old Eng. Law.) A tax on every plow or plowland.
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   2. The act of plowing. [R.]
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