frisco I. frisconoun (-es) Etymology: probably alteration of frisk (I) + -o (common Spanish & Italian noun ending) obsolete: friscal II. fris·co\ˈfri(ˌ)skō\adjective Usage: usually capitalized Etymology: from Frisco, short for San Francisco, Calif. slang: of or relating to the city of San Francisco, Calif. < the Frisco convention >