The Greek verb optanomai (ὀπτάνομαι) means to appear, to be seen, or to show oneself. It is a middle/passive deponent form related to horao (to see, G3708) and optomai. In the New Testament it is almost exclusively used of post-resurrection appearances of Jesus Christ — making it a specialized theological vocabulary word for the Easter witness.
The theological significance of optanomai centers on the resurrection appearances of Christ. Acts 1:3 uses it: Jesus 'appeared (optanomenos) to them over a period of forty days.' In Acts 13:31, Paul anchors the gospel proclamation in the fact that Jesus 'was seen (ophthē) for many days by those who had traveled with him from Galilee to Jerusalem.' The crucial passage is 1 Corinthians 15:5–8, listing those to whom the risen Christ 'appeared' (ophthē). Each appearance is a ground of apostolic testimony — the gospel is not philosophy but eyewitness report. The resurrection is an event in history, verified by sight. The New Testament's careful use of vision vocabulary for resurrection appearances anchors faith in historical, embodied reality.