Pronunciation: (sub-nôr'mul),[key] —adj. 1. below the normal; less than or inferior to the normal: a subnormal amount of rain. 2. being less than average in any psychological trait, as intelligence, personality, or emotional adjustment.
—n. 1. a subnormal person.
2. Geom.that part of the x-axis of a curve cut off between the ordinate and a normal.