inner hearth[¦in·ər ′härth]
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
back hearth, inner hearth
That part of the hearth, or floor, which is contained within the jambs of the fireplace.
That part of a hearth contained within a fireplace; the back hearth.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.