Lift (statistical association)
The ratio of how often two things actually occur together to how often you'd expect them to occur together by chance alone, given how common each one is individually. A lift of 1.0 means no relationship; above 1.0 means the pair travels together more than chance predicts; below 1.0 means less.
Example
N-Acetylcysteine (NAC) and Quercetin are declared together 7.38x more often than chance would predict -- the highest lift of any compound pair we track.