trass

American  

[tras] / træs /

noun

1. a light-colored type of volcanic tuff used in making water-resistant cement and mortar.

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trass British  

/ træs /

noun

1. a variety of the volcanic rock tuff, used to make a hydraulic cement

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Etymology

Origin of trass

First recorded in 1790–1800; from Dutch trass, from earlier terass, tieras, tiras “brick dust, rubbish,” from French terrasse; terrace ( def. )

Example Sentences

In this case, also, the addition of finely-ground silica, or trass, improved the resisting power of blocks made with poor mortars, but did not have any appreciable effect on the stronger mixtures.

From The Sewerage of Sea Coast Towns by Adams, Henry C.

The tufaceous alluvium called trass, which has covered large areas in the Eifel, and choked up some valleys now partially re-excavated, is unstratified.

From The Student's Elements of Geology by Lyell, Charles, Sir

The village of Nippes owes its origin to the trade in trass, having been founded by a Dutchman, who settled there about a century ago for the convenience of exportation.

From The Mirror of Literature, Amusement, and Instruction Volume 12, No. 326, August 9, 1828 by Various

If, as is probable, this trass was formed during the period of volcanic eruptions, it may have originated in the manner of the moya of the Andes.

From The Student's Elements of Geology by Lyell, Charles, Sir

The idea of the trass having any connexion with a deluge, is, I believe, now exploded; and geologists have agreed that it is the actual substance ejected by the volcano, subsided into a firm paste.

From The Mirror of Literature, Amusement, and Instruction Volume 12, No. 326, August 9, 1828 by Various