Source : Webster's Revised Unabridged Dictionary (1913)

Nanism \Na"nism\, n. [Gr. ? + -ism: cf. F. nanisme.]
   The condition of being abnormally small in stature;
   dwarfishness; -- opposed to {gigantism}.

Source : WordNet®

nanism
     n : a genetic abnormality resulting in short stature [syn: {dwarfism}]