Hadath:

Literally means "impurity". Hadath is of two types; hadath-e-akbar and hadath-e-asghar. Hadath-e-akbar is that impurity which necessitates ghusl. Hadath-e-asghar is that impurity which necessitates wudu.

Hadith:

Hadith literally means "speech". In Islam it refers to the sayings and actions of Rasulullah sallallahu alayhi wa sallam. Those sayings and actions which have been endorsed or approved by him also fall under the purview of Hadith.

Haid:

Monthly periods or menstruation experienced by a woman.

Hajj:

Literally means "pilgrimage". In Islam it refers to the annual pilgrimage to Makkah. Hajj is the fifth pillar of Islam.

Hijaab:

See Purdah.