Definition - What does Sustained mean?
To sustain is to agree with or to approve something.
In the context of the law, the term "sustain" is commonly used when a judge agrees with an objection made by an attorney. When an objection is sustained, it means that the judges approves of it and agrees with the lawyer who made it.
Justipedia explains Sustained
If an objection is not sustained, it will be overruled. If an objection is overruled, then it means that the judge disagrees with the lawyer who made it, and grants permission to the opposing counsel to carry on as they were doing.
Attorneys often make objections if they believe that the opposing counsel is doing something that is unlawful, such as leading the witness in certain circumstances where it is not allowed. Whether an objection is sustained or overruled can sometimes have very strong implications for a trial.