through arch[′thrü ‚ärch]
An arch bridge from which the roadway is suspended as distinct from one which carries the roadway on top.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
Any arch which is set in a thick, heavy wall.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.