al·to·strat·us (ăl′tō-strătəs, -strātəs)
An extended cloud formation of bluish or gray sheets or layers.
[Latin altus, high; see al-2 in the Appendix of Indo-European roots + STRATUS.]
(click for a larger image)altostratus
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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:
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