Extramuros
From Anathem Wiki
Saecular society outside of the maths.
[edit] Meaning
Literally everything "Outside of the Walls" of the concent.
[edit] Speculation
The old part of Manila, called the Intramuros (lit. "Inside the Walls") may have been an inspiration, as the location plays a part in Cryptonomicon, though intramuros and extramuros are terms that have been used to describe sections of many walled cities around the world.
