• WordNet 3.6
    • n firebrick brick made of fire clay; used for lining e.g. furnaces and chimneys
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Century Dictionary and Cyclopedia
    • n firebrick A brick made of material which will not fuse readily in a kiln or furnace: used for lining furnaces, etc.
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Chambers's Twentieth Century Dictionary
    • Firebrick a brick so made as to resist the action of fire, used for lining furnaces, &c
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Chambers's Twentieth Century Dictionary
A.S. fýr; Ger. feuer; Gr. pyr.


In literature:

The same result could be obtained by a pile of red-hot lumps of firebrick, and the same heat obtained also without a trace of flame.
"Scientific American Supplement, No. 430, March 29, 1884" by Various
There are no firebars at the bottom, so that the fuel rests on a floor of firebrick.
"Scientific American Supplement, No. 401, September 8, 1883" by Various
Few, if any, samples of firebrick will stand the heat of this blast, if the system is fully utilized.
"Scientific American Supplement, No. 481, March 21, 1885" by Various
This favoured region supplies also most of the fluxes required for the manufacture of steel, and even clays for firebricks.
"India, Old and New" by Sir Valentine Chirol
No; depending upon the heat from the firebricks to re-light the fire is dangerous and forbidden.
"The Traveling Engineers' Association" by Anonymous
They look something like bandboxes made of firebrick.
"Illustrated Science for Boys and Girls" by Anonymous
There is nothing really better as a radiating surface than ordinary firebrick.
"The Turkish Bath" by Robert Owen Allsop
The whole is enclosed in firebrick casing.
"Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 2" by Various
The furnace in which this operation is carried out is a tall, vertical cylinder of iron, lined with firebrick.
"The Romance of War Inventions" by Thomas W. Corbin
Ordinary firebricks are made from fireclays, i.e.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 4" by Various
Coarse-grained but very strong firebricks are also made of the waste of china clay works.
"Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 3" by Various
Firebricks were used for the fireholes, flues, floor, core, and dome; strong stock bricks for the rest.
"Pottery, for Artists Craftsmen & Teachers" by George J. Cox

In news:

Holes in the lid each include a firebrick crucible cover.
Three-inch-high temperature K-25 firebrick is used throughout the kiln.
One hand-built firebrick oven later, it's time to dig in.