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tra·che·ole

(trākē-ōl′)

One of the very small, branching tubes at the tips of the tracheae of an arthropod. Oxygen and carbon dioxide diffuse through the walls of the tracheoles.

[New Latin trāchēola, diminutive of Medieval Latin trāchēa, trachea; see TRACHEA.]

tra·cheo·lar (-ə-lər) adj.

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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