Source : Webster's Revised Unabridged Dictionary (1913)

Fireplace \Fire"place`\, n.
   The part a chimney appropriated to the fire; a hearth; --
   usually an open recess in a wall, in which a fire may be
   built.

Source : WordNet®

fireplace
     n : an open recess in a wall at the base of a chimney where a
         fire can be built; "the fireplace was so large you could
         walk inside it"; "he laid a fire in the hearth and lit
         it"; "the hearth was black with the charcoal of many
         fires" [syn: {hearth}, {open fireplace}]