This noun denotes someone who has seen with their own eyes—an eyewitness or personal observer. In 2 Peter 1:16, the apostles claim to be eyewitnesses of Christ's majesty at the Transfiguration, not following cleverly devised myths. Classical usage included overseers and watchers (especially gods observing human affairs) and those initiated into the highest grade of mystery religions. The New Testament appropriates this language of privileged seeing for apostolic witness. The multilingual evidence is consistent: eyewitnesses, testigos oculares (eye witnesses), Augenzeuge—all emphasizing direct visual testimony.