What does GRK stand for?

Gear Rack

Golden Rock Resources Ltd. - Vancouver Stock Exchange symbol

Goroka - Papua New Guinea - Seismograph station code, US Geological Survey - Closed (SEIS)

G Protein Receptor Kinase - An enzyme

Greek - Language code (ETLW)

Greenville Fiberglass Co., Greenville, SC - Manufacturer code for watercraft hull identification number (USCG)

Killeen, TX - Location identifier - FAA (FAAL)