lahar?

Another Friday afternoon in the 5th grade, another stumper!  

Do YOU know what lahar means?  Here's a hint:

Still stumped, like me?

"A lahar is a type of mudflow or debris flow composed of a slurry of pyroclastic material, rocky debris, and water.  The material flows down from a volcano, typically along a river valley." 

(When I got home I quizzed geologist hubby Tom, and, as expected, he was familiar with the term.)

The picture below, of the mudline left behind on the trees on the banks of the Muddy River after the 1980 eruption of Mount St. Helens, shows how high the lahars reached there.

And now you've learned a new word!