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co·lon bacillus

(kōlən)

A rod-shaped bacterium, especially Escherichia coli, that is normally present and nonpathogenic in the intestinal tracts of vertebrates but can cause diarrhea and other gastrointestinal symptoms.

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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