Glossary
Objection
A formal statement to the court that opposing counsel is doing something improper: usually asking an improper question or trying to introduce inadmissible evidence. The judge rules immediately.
Lawyers stand up and say "Objection, Your Honor: leading," or "Objection: hearsay," or one of dozens of standard formulations. The judge then either says "sustained" (the objection is good, the question or evidence is not allowed) or "overruled" (the question or evidence is allowed).
If you don't object at the right time, you can lose the right to complain about it on appeal. Objections have to be timely and specific: saying "I don't like that" doesn't count.