na·nism \ˈnāˌnizəm, ˈnaˌ-\noun (-s) Etymology: French nanisme, from nan- + -isme -ism : the condition of being abnormally or exceptionally small in stature : dwarfishness — opposed to gigantism < the nanism of the early generations of nonsexual castes of many social insects results from food shortage in a new or weak colony >