noun: (US, aviation) Prefix code for NASA research fighter plane designations.
noun: (Canada) Initialism of Newfoundland and Labrador, a Canadian province. [A province in eastern Canada. Capital: St. John's.]
noun: (US, pharmacology) Initialism of National Formulary, a book of public pharmacopeial standards.
adjective: (slang) Initialism of not frat, denoting things counter to the culture of Greek life, particularly in the Southern United States
noun: (pathology) Initialism of necrotizing fasciitis. [A severe, fast-spreading infection that results in the death of the body's soft tissue.]
noun: (pathology) Initialism of neurofibromatosis. [(medicine) A genetic disorder characterized by the presence of multiple neurofibromas under the skin.]