Also found in: Thesaurus, Acronyms, Encyclopedia, Wikipedia.
Related to tuff: tough
A rock composed of compacted volcanic ash varying in size from fine sand to coarse gravel.
[French tuf, from Old French, from Old Italian tufo, tufa; see tufa.]
tuff·a′ceous (tŭ-fā′shəs) adj.
(Geological Science) a rock formed by the fusing together on the ground of small rock fragments (less than 2 mm across) ejected from a volcano
[C16: from Old French tuf, from Italian tufo; see tufa]
a fragmental rock consisting of the smaller kinds of volcanic detritus, as ash or cinder, usu. more or less stratified.
[1560–70; < Middle French tuf(e) < Italian tufo. See tufa]
A rock made up of particles of volcanic ash, varying in size from fine sand to coarse gravel.
A rock made up of compacted volcanic ash; also known as tufa.