so·lar·i·um (sō-lârē-əm, sə-)
n. pl. so·lar·i·a (-ē-ə) or so·lar·i·ums
A room, gallery, or glassed-in porch exposed to the sun.
[Latin sōlārium, terrace, flat housetop, from sōl, sun; see sāwel- in the Appendix of Indo-European roots.]
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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:
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.