- neptunium, Np, atomic number 93 - a radioactive transuranic metallic element; found in trace amounts in uranium ores; a by-product of the production of plutonium
--1 is a kind of metallic element, metal
- nurse practitioner, NP, nurse clinician - a registered nurse who has received special training and can perform many of the duties of a physician
--2 is a kind of registered nurse, RN