Home › Words › R › ronnagramronnagramronnagram · noun — an SI unit of mass equal to 10²⁷ grams. Symbol: Rg.Definition from Wiktionary (CC BY-SA 3.0).Among words judged in Lexicurio's Arena, ronnagram ranks #32,100 of 43,221 for Qualifying.EtymologyFrom ronna- + gram.nounAn SI unit of mass equal to 10²⁷ grams. Symbol: Rge.g.“The Earth weighs about six ronnagrams.”Definitions & examples from Wiktionary (CC BY-SA 3.0).