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loup·ing ill

(loupĭng, lō-)

An infectious neurological disease chiefly of sheep, caused by a flavivirus that is transmitted by the sheep tick. It is characterized by a jerky, hopping gait and often prolonged trembling.

[From Scots loup, to leap, from Middle English lopen; see LOPE.]

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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