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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The Collaborative International Dictionary of English v.0.48:

Potent \Po"tent\, a. [L. potens, -entis, p. pr. of posse to be
   able, to have power, fr. potis able, capable (akin to Skr.
   pati master, lord) + esse to be. See Host a landlord, Am,
   and cf. Despot, Podesta, Possible, Power,
   Puissant.]
   1. Producing great physical effects; forcible; powerful'
      efficacious; as, a potent medicine. "Harsh and potent
      injuries." --Shak.
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            Moses once more his potent rod extends. --Milton.
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   2. Having great authority, control, or dominion; puissant;
      mighty; influential; as, a potent prince. "A potent
      dukedom." --Shak.
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            Most potent, grave, and reverend signiors. --Shak.
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   3. Powerful, in an intellectual or moral sense; having great
      influence; as, potent interest; a potent argument.
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   Cross potent. (Her.) See Illust. (7) of Cross.
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   Syn: Powerful; mighty; puissant; strong; able; efficient;
        forcible; efficacious; cogent; influential.
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WordNet (r) 3.0 (2006):

potent
    adj 1: having great influence [syn: potent, powerful]
    2: having or wielding force or authority; "providing the ground
       soldier with increasingly potent weapons" [syn: potent,
       strong]
    3: having a strong physiological or chemical effect; "a potent
       toxin"; "potent liquor"; "a potent cup of tea", "a stiff
       drink" [syn: potent, strong, stiff] [ant: impotent]
    4: (of a male) capable of copulation [syn: potent, virile]
       [ant: impotent]