It's often used in medical terms to describe a condition where a part of the body has reduced strength or function.
Here are some examples:
* hemiparesis: Weakness on one side of the body
* quadriparesis: Weakness in all four limbs
* paraparesis: Weakness in the legs
* facial paresis: Weakness in the facial muscles
The term paresis is often used in contrast to plegia, which refers to complete paralysis.