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spi·ro·plas·ma

(spīrə-plăz′mə)

Any of various small spiral-shaped bacteria of the genus Spiroplasma that lack a cell wall, move by means of a flexing motion, and cause diseases in some plants and insects.

[New Latin Spīroplasma, genus name : Latin spīra, coil; see SPIRE² + PLASMA.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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