n. pl. ef·flu·vi·a (-vē-ə) or ef·flu·vi·ums
1. A usually invisible emanation or exhalation, as of vapor or gas.
a. A byproduct or residue; waste.
b. The odorous fumes given off by waste or decaying matter.
3. An impalpable emanation; an aura.
[Latin, from effluere, to flow out; see EFFLUENT.]
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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.