from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Calcareous tufa, a porous or spongy deposit of calcium carbonate found in calcareous mineral springs.
from the GNU version of the Collaborative International Dictionary of English
- n. See under calcite.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a soft porous rock consisting of calcium carbonate deposited from springs rich in lime
calc(areous) + tufa.(American Heritage® Dictionary of the English Language, Fourth Edition)
ALABASTER) and other stalagmitic deposits also consist of calcite, and so do the allied deposits of travertine, calc-sinter or calc-tufa.