Source : Webster's Revised Unabridged Dictionary (1913)

Coal \Coal\, n. [AS. col; akin to D. kool, OHG. chol, cholo, G.
   kohle, Icel. kol, pl., Sw. kol, Dan. kul; cf. Skr. jval to
   burn. Cf. {Kiln}, {Collier}.]
   1. A thoroughly charred, and extinguished or still ignited,
      fragment from wood or other combustible substance;
      charcoal.

   2. (Min.) A black, or brownish black, solid, combustible
      substance, dug from beds or veins in the earth to be used
      for fuel, and consisting, like charcoal, mainly of carbon,
      but more compact, and often affording, when heated, a
      large amount of volatile matter.

   Note: This word is often used adjectively, or as the first
         part of self-explaining compounds; as, coal-black; coal
         formation; coal scuttle; coal ship. etc.

   Note: In England the plural coals is used, for the broken
         mineral coal burned in grates, etc.; as, to put coals
         on the fire. In the United States the singular in a
         collective sense is the customary usage; as, a hod of
         coal.

   {Age of coal plants}. See {Age of Acrogens}, under {Acrogen}.
      

   {Anthracite} or {Glance coal}. See {Anthracite}.

   {Bituminous coal}. See under {Bituminous}.

   {Blind coal}. See under {Blind}.

   {Brown coal}, or {Lignite}. See {Lignite}.

   {Caking coal}, a bituminous coal, which softens and becomes
      pasty or semi-viscid when heated. On increasing the heat,
      the volatile products are driven off, and a coherent,
      grayish black, cellular mass of coke is left.

   {Cannel coal}, a very compact bituminous coal, of fine
      texture and dull luster. See {Cannel coal}.

   {Coal bed} (Geol.), a layer or stratum of mineral coal.

   {Coal breaker}, a structure including machines and machinery
      adapted for crushing, cleansing, and assorting coal.

   {Coal field} (Geol.), a region in which deposits of coal
      occur. Such regions have often a basinlike structure, and
      are hence called {coal basins}. See {Basin}.

   {Coal gas}, a variety of carbureted hydrogen, procured from
      bituminous coal, used in lighting streets, houses, etc.,
      and for cooking and heating.

   {Coal heaver}, a man employed in carrying coal, and esp. in
      putting it in, and discharging it from, ships.

   {Coal measures}. (Geol.)
      (a) Strata of coal with the attendant rocks.
      (b) A subdivision of the carboniferous formation, between
          the millstone grit below and the Permian formation
          above, and including nearly all the workable coal beds
          of the world.

   {Coal oil}, a general name for mineral oils; petroleum.

   {Coal plant} (Geol.), one of the remains or impressions of
      plants found in the strata of the coal formation.

   {Coal tar}. See in the Vocabulary.

   {To haul over the coals}, to call to account; to scold or
      censure. [Colloq.]

   {Wood coal}. See {Lignite}.