What does RIV stand for?

What does RIV mean?

RIV	River Academic & Science » Ocean Science
RIV	Riviera Governmental » Transportation
RIV	Region IV Miscellaneous » Toastmasters
RIV	Riviera Holdings Corporation Business » AMEX Symbols
RIV	Registrar of Imported Vehicles Governmental » Transportation
RIV	Registrar of Imported Vehicles Governmental » US Government
RIV	Registrar of Imported Vehicles Business » International Business
RIV	Recirculation Isolation Valve Governmental » NASA
RIV	Radio Interference Voltage Academic & Science » Amateur Radio