'Ghost' in the Bible

Then you shall be low; you shall speak from [the] earth, and your words will be low, from dust. And your voice will be from [the] earth, like a ghost, and your word will whisper from [the] dust.

But the disciples, [when they] saw him walking on the sea, were terrified, saying, "It is a ghost!" and they cried out in fear.

But [when] they saw him walking on the sea, they thought that it was a ghost, and they cried out.

But they were startled and became terrified, [and] thought [they] had seen a ghost.

Look at my hands and my feet, that I am I myself! Touch me and see, because a ghost does not have flesh and bones, as {you see that I have}."