(law) A doctrine of law holding that a court should decline to hear a case if another court—especially one in a foreign jurisdiction—would provide a more appropriate forum for the parties and evidence.

(law, but also seeing wider use) Insane; not of sound mind; not in control of oneself.

(medicine) Coeliac disease.

(Canadian military) A members of the Canadian Forces that is not a commissioned officer; includes warrant officers, non-commissioned officers and privates.

(art) perception of an object without known points of reference.

plural of persona non grata

Service in a non-military organisation, instead of serving in the military. Service done by conscientious objector.

plural of non-player character

(computing theory) A symbol in a formal grammar that cannot appear in sentences of the grammar but may eventually be resolved into a sequence of terminal symbols.

(computing) A requirement of a piece of software, such as accessibility or portability, that is not a specific, measurable aspect of performing a particular task.