tuff

¹ American  

[tuhf] / tʌf /

adjective

Slang.

1. tough.

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tuff ² American  

[tuhf] / tʌf /

noun

Geology.

1. a fragmental rock consisting of the smaller kinds of volcanic detritus, as ash or cinder, usually more or less stratified.

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tuff British  

/ tʌf, tʌˈfeɪʃəs /

noun

1. a rock formed by the fusing together on the ground of small rock fragments (less than 2 mm across) ejected from a volcano

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tuff Scientific  

/ tŭf /

1. A rock made up of particles of volcanic ash, varying in size from fine sand to coarse gravel.

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Other Word Forms

• tuffaceous adjective

Etymology

Origin of tuff

1560–70; < French tuf < Italian tufo. See tufa

Example Sentences

The petroglyphs can be found on volcanic tuff formations formed over 760,000 years ago when a large eruption released hot ash that settled over the region.

From Los Angeles Times

First with photos and drawings and later with a 3D scanner, the marks in the tuff rock of the cave wall were meticulously recorded.

From Science Daily

The trilobite fossils were trapped between layers of petrified ash in sandstone, the product of old volcanic eruptions that settled on the sea floor and formed a green layer called a tuff.

From Science Daily

The river tracks a diverse landscape from the southern edge of the Rocky Mountains through rugged basalt hillsides, layers of volcanic tuff, and the red and yellow cliffs made famous by painter Georgia O’Keeffe.

From Seattle Times

The point is “GOATs” do not quit when the going gets tuff.

From Los Angeles Times