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

Derived Forms

• tuffaceous
  adjective

Etymology

Origin of tuff

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