syndrome X

noun

-ˈeks 

1

: angina pectoris of a usually benign form in which the coronary arteriogram is normal

2

: metabolic syndrome

Metabolic syndrome, sometimes called syndrome X, was first defined in 1988 as a collection of health risks that may increase the chances of developing cardiovascular disease two-and-a-half to four times, and diabetes by four to six times.

—Catherine Arnst, Business Week