case bay[′kās ‚bā]
A division of a roof or floor, consisting of two principal rafters and the joists between them.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
That section of a floor or roof between two principals or girders.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.