endometriosis

noun

1. a medical condition in which tissue similar to the lining of the uterus grows outside the uterus, often causing pain and sometimes fertility problems.

   B2

   uncountable

   • "She has endometriosis and often experiences severe period pain."B1
   • "Endometriosis can affect the ovaries, fallopian tubes, and other tissues in the pelvis."B2
   • "Researchers are studying why endometriosis develops and how it can be treated more effectively."C1