cu·mu·lus  (ky m y ə-l əs)
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n. pl. cu·mu·li (-l ī′) 1. A dense, white, fluffy, flat-based cloud with a multiple rounded top and a well-defined outline, usually formed by the ascent of thermally unstable air masses. 2. A pile, mound, or heap.
 (click for a larger image) cumulus |
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Indo-European & Semitic Roots Appendices
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