Thysanura

Webster's Dictionary of the English Language

·noun ·pl An order of wingless hexapod insects which have setiform caudal appendages, either bent beneath the body to form a spring, or projecting as bristles. It comprises the Cinura, or bristletails, and the Collembola, or springtails. Called also Thysanoura. ·see Lepisma, and Podura.