In a message dated 98-06-08 01:09:13 EDT, you write:

<< Amazingly, the OED has no entry for wythe, except as an obsolete  spelling
 for white and with (wythe a brief stopover at withe). >>

We've been going at this a wythetime.

OK, _Construcution Glossary_, J. Stewart Stein, Wiley, 1980

Wythe (leaf)
1. Each continuous vertical section of a wall, 1 masonry unit in thickness and
tied to its adjacent vertical section or sections (front or back) by bonders
(headers), metal ties, or grout.
2. Thickness of masonry separating flues in a chimney.
3. Four-inch partition or tie between two walls, such as two walls of a
chimney.

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