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.
Poor, shoddy; less than second-rate.
Of a Royal Navy ship of the line in the Napoleonic Era: having 64–80 guns across two gun decks, a complement of 500–650, and weighing approximately 1,750 tons burthen.
A third-rate ship of the line.