Chief of petitioner- definition in family court

Hello Everyone,

The hearing on next date is listed as Chief of Petitioner in the website of the Family court. The definition on the website says as follows:

N.B.W.(READY):- When Non bailable warrant is issued against accused in a case at the middle stage of the trial, i.e. When matter is ready/effective, this stage is given either for issuing such NBW or awaiting report of the same.

What does this mean?

Thanks.