noun

• An official indicator that things will happen as planned.
• A verification that something is true or has happened.
• A ceremony of sealing and conscious acknowledgement of the faith in many Christian churches, typically around the ages of 14 to 18; considered a sacrament in some churches, including Catholicism, but not in most Protestant churches.
• (law) An act whereby something conditional or voidable is made sure and unavoidable, especially the possession of an estate.