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tel·lu·ri·um (tĕ-lrē-əm)
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n. Symbol Te
A brittle, silvery-white, rare metallic element usually found in combination with gold and other metals, produced commercially as a byproduct of the electrolytic refining of copper and used in compact discs, semiconductors, ceramics, and blasting caps and (in the form of bismuth telluride) in thermoelectric devices. In alloys it improves the machinability of stainless steel or copper, and increases the durability and hardness of lead. Atomic number 52; atomic weight 127.60; melting point 449.5°C; boiling point 988°C; specific gravity 6.23 (20°C); valence 2, 4, 6. See Periodic Table.

[From Latin tellūs, tellūr-, earth (by contrast with uranium, under a conception of the latter as an element of the heavens because of its being named after the planet Uranus).]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 

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.