What is "gall stones"

Usage examples of "gall stones".

I've attempted suicide, had homicide attempted against me, had gall stones and kidney stones and driven on sharp stones that shredded my tires.

I didn't understand a word of the spell, as it was spoken in some lost language that delighted in words ending in -- vowel-t-h and other vocabulary that was so guttural that you could get gall stones just listening to it.