Definition - What does Your Honor mean?
The term 'your honor' is a designation of a judge that is presiding over a case. The term is used when either the prosecution or the defense speaks directly to the judge. It can also mean the respect that is afforded to a person of authority. The reason the term is used when prosecution and defense attorneys speak is to signify that they understand that the judge is above them in the situation and acts as a recognition of the process that is occurring.
Justipedia explains Your Honor
The only people in a court room that have the right to speak directly to the judge is the bailiff that is presiding in the courtroom and the attorneys present to represent the parties involved. The judge is the top person in the court room whether or not a jury is in place. Admissions made directly to them are done with the utmost of respect. The term is as old as Middle English and has always been used in English and US law.