Deiknumi (δείκνυμι) means to show or demonstrate — to make something visible, to point it out, to prove it by evidence. It covers: physical pointing ('show me the place'), visual revelation (God showing Moses the land), demonstrating through argument, and the apocalyptic 'showing' of divine visions.
John's Gospel uses deiknumi in the profound statement of Jesus: 'The Son can do nothing of himself, but only what he sees the Father doing. For whatever the Father does, the Son does likewise. For the Father loves the Son and shows him everything that he himself is doing' (John 5:19-20). The Son's ministry is a revelation of what the Father shows — divine communication within the Trinity expressed as mutual showing. Revelation uses the word for the Angel 'showing' John the visions: 'Come, I will show you' (Revelation 17:1; 21:9). James 2:18 challenges without works: 'Show me your faith apart from your works' — deiknumi as proof-by-demonstration.
Jesus's post-resurrection 'showing' of His wounds (John 20:20) is a decisive moment: deiknumi used for the evidence of the resurrection — hands and side that bore real wounds from a real cross. Faith is not blind; it is grounded in what God has shown. The entire Book of Revelation is structured as a 'showing' (apokalupsis — uncovering/revealing), and deiknumi structures its visionary tours. God's ultimate purpose is to 'show' His glory to the nations — the entire story of Scripture is this grand display.