msau

from The Free On-line Dictionary of Computing (8 July 2008)

Media Access Unit
MAU
MSAU
Multistation Access Unit

   <networking> (MAU or Multistation Access Unit, MSAU) In a
   {Token Ring} network, a device to attach multiple network
   stations in a star topology, internally wired to connect the
   stations into a logical ring.  The MAU contains relays to
   short out nonoperating stations.  Multiple MAUs can be
   connected into a larger ring through their Ring In/Ring Out
   connectors.

   (1997-05-27)