Definition of "tuff" [tuff]

• A rock composed of compacted volcanic ash varying in size from fine sand to coarse gravel. Also called tufa. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "To the hypocrite Christopher Dodd sitting there saying we are going to get tuff is hilarious."
• "Over time, that ash became a rock called tuff, which is anything but: tuff is soft, crumbly, and erodes easily."
• "Sometimes called tuff, it had often been used on Earth as construction material."