Home › Words › F › firtreefirtreefirtree · noun — A fir.Definition from Wiktionary (CC BY-SA 3.0).Among words judged in Lexicurio's Arena, firtree ranks #2,501 of 43,053 for Qualifying.EtymologyFrom fir + tree.nounA fir.The root of a very-high-temperature turbine blade, inserted into a corresponding slot in a disc, resembling in section a simplified image of a fir.Definitions & examples from Wiktionary (CC BY-SA 3.0).