perforated brick (Brit.)
A brick or block in which holes passing through it exceed 25% of its volume, and in which the holes are not small (as defined under solid masonry unit, 2); up to three holes, not exceeding 5 sq in. (32.5 sq cm) each, may be incorporated as an aid to handling.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.