tu·fa (tfə, ty-)
A soft, friable, and porous sedimentary rock consisting of calcium carbonate and formed by the evaporation of water, especially at the mouth of a hot spring or on a drying lakebed. It can also be precipitated by algae or bacteria.
[Obsolete Italian tufa, tufo, from Latin tōfus.]
tu·faceous (-fāshəs) adj.
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Indo-European & Semitic Roots Appendices
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