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tick ²

(tĭk)

1. Any of various small bloodsucking arachnids of the order Ixodida that are parasitic on terrestrial vertebrates. Many species transmit diseases, such as Rocky Mountain spotted fever and Lyme disease.

2. Any of various usually wingless insects that resemble a tick, such as a sheep ked.

[Middle English tike, tik, perhaps from Old English *ticca.]

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:

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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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