Less than normal.
denormal
A person whose abilities are less than normal.
That part of the axis of a curved line which is intercepted between the ordinate and the normal.
Small and weak.
Consisting of weeds.
Characteristic of a plant that grows rapidly and spreads invasively, and which grows opportunistically in cracks of sidewalks and disturbed areas.
Abounding with weeds.
Of, relating to or resembling weeds.
Lacking power or effectiveness.