Was trying to describe that PMS symptom to DP which resulted in half an hour of bewildered back and forthing ("but you must be able to describe it!"): you know, its not an ache or pain in your ovaries at all, just like a pressure or tightening in your pelvis, not even that, like a fizzying weight.
I vote each poster describes the indescribable and then sets their own indescribable for the next poster.
Here we go!
Describe thirst.