The Collaborative International Dictionary of English v.0.48:

Charger \Char"ger\, n.
   1. One who, or that which charges.
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   2. An instrument for measuring or inserting a charge.
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   3. A large dish. [Obs.]
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            Give me here John Baptist's head in a charger.
                                                  --Matt. xiv.
                                                  8.
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   4. A horse for battle or parade. --Macaulay.
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            And furious every charger neighed.    --Campbell.
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WordNet (r) 3.0 (2006):

charger
    n 1: formerly a strong swift horse ridden into battle [syn:
         charger, courser]
    2: a device for charging or recharging batteries [syn:
       charger, battery charger]