Webster’s Revised Unabridged Dictionary · 1913
Thysanura
Thys′a·nu′ra, n. pl. [NL., fr. Gr. θύσανος fringe + οὐρά tail.] (Zoöl.) 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.