from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A fine-grained quartzite used to line refractory furnaces.
- n. A mixture of fire clay and ground quartz, used to line metallurgical furnaces.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A hard, fine-grained sandstone, used in manufacturing silica bricks for lining furnaces.
from the GNU version of the Collaborative International Dictionary of English
- n. A refractory material consisting of crushed or ground siliceous stone, mixed with fire clay; -- used for lining Bessemer converters; also used for macadamizing roads.
from The Century Dictionary and Cyclopedia
- n. In mining and metallurgy, a hard, silicious rock forming the floor of some coal-seams in England.
Origin unknown.(American Heritage® Dictionary of the English Language, Fourth Edition)
The origin of this word is unknown. (Wiktionary)