Cnemidophorus is a genus of lizards in the family Teiidae. Species in the genus Cnemidophorus are commonly referred to as whiptail lizards or racerunners. Note that the nomenclature for this genus has recently been re-examined by T.W. Reeder et al. in 2002. Many species that were Cnemidophorus should now likely be considered Aspidoscelis based upon divergent characters between the two groups. The name Cnemidophorus literally means "greave-wearing", from the Ancient Greek knēmido- (combining form of knēmis, "greave", a leg armor) and -phoros ("bearer").