thy·sa·nu·ran (thī′sə-nrən, -nyr-)
Any of various wingless insects of the order Thysanura, which is usually defined as consisting solely of the silverfish and excluding bristletails of the order Archaeognatha.
[From New Latin Thysanūra, order name : Greek thusanos, tassel + Greek ourā, tail; see ors- in the Appendix of Indo-European roots.]
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Indo-European & Semitic Roots Appendices
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