The Collaborative International Dictionary of English v.0.48:

Potent \Po"tent\, n.
   1. A prince; a potentate. [Obs.] --Shak.
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   2. [See Potence.] A staff or crutch. [Obs.]
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   3. (Her.) One of the furs; a surface composed of patches
      which are supposed to represent crutch heads; they are
      always alternately argent and azure, unless otherwise
      specially mentioned.
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   Counter potent (Her.), a fur differing from potent in the
      arrangement of the patches.
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