Recirculating Infusion Mash System. If you can't see calling regular kitchen appliances a "brewery," you'll wind up with one of these. There are many designs, but most involve a pump that moves mash water around and around through the grain. This gives more temperature consistency and better filtration.
Abbreviation for Recirculating Infusion Mash System. The continuous re-circulation of the thin mash to maintain or increase mash temperature. Heat is applied to the thin mash outside of the Mash Tun. Traditionally, a heating chamber with an electric heater is used.
Recirculating Infusion Mash System - brewing setup that is quite popular among homebrewers.