The wood window frame of a double-hung window, including the sash pockets.
Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved
cased frame, boxed frame, box frame
The wood frame of a double-hung window; has hollow jambs or mullions which contain the sash counterweights.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.