The Collaborative International Dictionary of English v.0.48:

Coal \Coal\, v. t. [imp. & p. p. Coaled; p. pr. & vb. n.
   Coaling.]
   1. To burn to charcoal; to char. [R.]
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            Charcoal of roots, coaled into great pieces.
                                                  --Bacon.
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   2. To mark or delineate with charcoal. --Camden.
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   3. To supply with coal; as, to coal a steamer.
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