Dul-Hajj is the last month and a sacred month of the Islamic calendar. The word ‘Dul-Hajj’ means ‘the month of Hajj’. It was in this month, the holy Prophet performed the farewell Hajj and the historic address known as ‘Farewell Sermon’. In this month Muslims perform the Hajj, the fifth pillar of
Islam, on the first ten days.
Dul-Hajj is also spelt as Dhu al-Hijja, Zul-Hijjah, Dhul-Hijja and Dhil-Hijja.
[Source all india (80) 24-Apr-05]