Tomorrow slip

The Advocates used to request the Judge during motions for listing their cases .Accepting the request the judge used to give slip to the registry to list those cases.This is what you mean.

respected sir,

The tentative date on which the case will be heard before the court is called a listing date and USR is unstamped register number which is provided to the document filed by either of the parties but not yet admitted in the court.

regards

Hello sir, greetings of the day.
As per your query, I am explaining you the meaning USR and tomorrow slip.
USR stands for Unstamped Register Number. It is a number which is provided to a document which has been filed by either of the parties but till now not admitted or numbered in the court. This reference number is used to trace the unique code of the lower court as the government tries for a merger with the soft wares of the ecourts and other courts. 
Tomorrow is also known as the listing date. It is the tentative date on which the case will be heard before the court. It implies that the case is coming up to the bench of judges for the hearing. Sometimes even though a particular case was supposed to be listed on a particular date, the court might not have listed the case citing the reason as presentation of a particular document or on account of huge number of pending cases.
Hope this information is useful.  
Regards
Nirali Nayak
Law Student