* and tree storage backends (SQL, CDB, and plain PHP arrays).
*
* All information is loaded on creation when called by $this->fetch( $prefix ).
- * All work is done on slave, because this should *never* change (except during
+ * All work is done on replica DB, because this should *never* change (except during
* schema updates etc, which aren't wiki-related)
*
* @since 1.28