It's a microsoft netbios master browser entry that is being truncated, _MSBROWSER_
This name is registered by the Master Browser and is used to broadcast and receive domain announcements on the local subnet. It is through this name that Master Browsers for different domains learn the names of different domains and the names of the Master Browsers on those domains. When a WINS Server receives a name query for this name, the WINS Server will always return the subnet broadcast address for the requesting client's local subnet.
My guess is you have a windows computer with netbios enabled on the network?