Nafl:

Literally means "optional". According to the jurists it has a similar ruling to that of mustahab.

Najaasat-e-ghaleezah:

Heavy impurity.

Najaasat-e-haqiqi:

Visible impurity.

Najaasat-e-hukmi:

Ceremonial impurity. In other words, it refers to the state of impurity in which a person may be, e.g. in need of wudu or ghusl.

Nazr:

A vow or solemn pledge.

Nifaas:

Refers to the flowing of blood after child-birth.

Nikah:

Marriage.

Niyyah:

Intention.

Nur:

Light.