A waiver is a formal statement giving up a right. If you go on a school trip, your mom might sign a waiver saying that the school is not responsible if you get hurt on the trip.
When you sign a waiver, you’re voluntarily giving up a privilege or legal right. A waiver is often required before you participate in something dangerous. If you decide to go skydiving, you might have to sign a waiver agreeing that you won’t sue the skydiving company if you get injured. That means you’re assuming all the risk associated with the activity. Other types of waivers can involve officially declining various rights, such as a privacy waiver or an insurance waiver.