Ziyarat, as mentioned in the question, refers to a specific meaning. The correct meaning of ziyarat is option 1, which is "pilgrimage to the tombs of sufi saints". This means that ziyarat is a practice where individuals visit the tombs or shrines of sufi saints as an act of devotion and seeking blessings.

Option 2, "the practice of revenue farming," is not the correct meaning of ziyarat. Revenue farming refers to a historical practice where the right to collect and manage revenue from a particular area or activity was leased or contracted out to individuals or groups.

Option 3, "the death anniversary of a sufi sheikh," is also not the right meaning of ziyarat. The term used for the death anniversary of a sufi sheikh is commonly known as "urs".

Option 4, "a form of Islamic divorce," is not the correct meaning either. Islamic divorce is typically referred to as "talaq" or "divorce".

Therefore, the correct meaning of ziyarat is the pilgrimage or visitation to the tombs of sufi saints.