Diddy Trial Will Not Be Delayed, Judge Denies Defense Motion

11:53 AM PT -- TMZ has learned "Victim 4" is someone who worked for Diddy, but was not romantically involved with him. We're told the defense argued they wanted that person's name revealed during the trial, so other potential witnesses could come forward with information that might refute the alleged victim's testimony.

Diddy's trial will proceed as scheduled ... 'cause a judge just ruled on his team's motion to delay the trial for two months -- and he's not giving them more time.

The hearing was held in New York City Friday, after Diddy's team accused prosecutors of turning over evidence too slowly ... asking the judge to grant more time so they could comb through all the discovery.

The judge disagreed with Diddy's side ... pointing out the rapper has four law firms representing him who should be able to sort through everything to be ready for the case by the scheduled May 5 start date.

As you know ... Diddy has been locked up in MDC Brooklyn -- a notorious federal jail in New York City -- since he was arrested at a Manhattan hotel in September.

He's facing five federal charges ... two counts of sex trafficking, two counts of transportation to engage in prostitution, and one count of racketeering.

Diddy has already pled not guilty to all the charges against him ... and, his legal team has proceeded to question major evidence in the case -- including the video of Diddy beating up Cassie in a hotel hallway.

Several alleged victims -- most of them anonymous -- plan to testify against Diddy when the trial kicks off ... including Cassie. While Cassie will use her own name, the judge ruled that "Victim 3" and "Victim 4" will go by pseudonyms and "Victim 2" will just be called "Victim 2."

On top of the criminal case, Diddy's dealing with a bunch of civil lawsuits too.