Tuff

This is what makes an ignimbrite; the general term for this kind of volcaniclastic rock is ‘tuff’.

Tuff Stuff teaches that while life may go smoothly most of the time, ...

… yet never to make us so strong as the strongest of Men, whose Sinnews are tuffer, and Bones stronger, and Joints closer, and Flesh firmer, than ours are …

It was rave reviewed in the Caribbean Times as 'the ruffest, tuffest and the boo-yacka of all modern gangster novels'.

Its Tuff-n-Tiny USB flash drive is about the size of a thumbnail. … The company insists that the "tuff" part of the name is well-earned for being waterproof, dustproof and you can drive a car over it.

Tuff Stuff Professional Wrestling