Final answer:
Orthopnea is a condition where a person experiences shortness of breath when lying flat, and they find relief when they sit up or stand.
Step-by-step explanation:
In medicine, if a patient has problems breathing in any other position other than sitting erect or standing, it is called orthopnea. Orthopnea is a condition where a person experiences shortness of breath when lying flat, and they find relief when they sit up or stand.