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tro·po·pause

(trōpə-pôz′, trŏpə-)

The boundary between the troposphere and the stratosphere varying in altitude from approximately 8 kilometers (5 miles) at the poles to approximately 18 kilometers (11 miles) at the equator.

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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