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Al·tair

(ăl-tīr, -târ, ăltīr′, -târ′)

A very bright, variable binary star in the constellation Aquila, approximately 15.7 light years from Earth. Altair is one of the stars that make up the Summer Triangle.

[Arabic (an-nasr) aṭ-ṭā'ir, the flying (eagle) : al-, the + ṭā'ir, flying, active participle of ṭāra, to fly; see ṭyr in the Appendix of Semitic roots.]

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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