friable

adj

1. Easily broken into small fragments, crumbled, or reduced to powder.

   “Spiders had woven their vague trapezes between the friable heads of dead peonies in enormous glass jars streaked with tide marks where the water had evaporated long ago.”

   “This light, friable type of material offered excellent insulation against both desert heat and also the cold of darkness during the winter.”

2. Of soil, loose and large-grained in consistency.

   “So while two men under his directions were digging the grave with sticks in the friable granitic soil, he superintended the costume of the other actors in the drama.”

3. Of a poison, likely to crumble and become airborne, thus becoming a health risk.

   “It is when asbestos-containing products are friable that hazardous asbestos fibers are likely to be released and sent airborne.”

4. Of a number: smooth, that factors completely into small prime numbers.