Word Study
limestone
CIDE DICTIONARY
limestone, n.
A rock consisting chiefly of calcium carbonate or carbonate of lime. It sometimes contains also magnesium carbonate, and is then called magnesian or dolomitic limestone. Crystalline limestone is called marble. [1913 Webster]
OXFORD DICTIONARY
limestone, n. Geol. a sedimentary rock composed mainly of calcium carbonate, used as building material and in the making of cement.
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