Synonyms for Nm (same or very similar meaning)
WordNet sense 1 (a metric unit of length equal to one billionth of a meter):
micromillimeter, micromillimetre, millimicron, nanometer, nanometre, NMWordNet sense 2 (a state in southwestern United States on the Mexican border):
New Mexico, Land of EnchantmentFrom the ODE community, based on WordNetadd/edit