olive grove: a piece of hillside planted with olive trees, and in the New Testament the ridge east of Jerusalem that took its name from them, the Mount of Olives
This is farm vocabulary before it is anything else. Greek builds a place word by adding an ending that means "a plot planted with": a plot of vines is a vineyard (ἀμπελών), and a plot of olive trees is this word. Everyday business papers from the same centuries use it for a registered piece of ground with olive trees standing on it, something you could buy, lease, tax, or leave to your children. So the picture underneath the word is working land, not scenery.
In the New Testament it belongs to one place only: the terraced ridge that rises east of Jerusalem across the Kidron valley, close enough that Acts measures the walk back into the city as a Sabbath day's journey. The hill was covered with olive trees, and it was named for them, which is why an ordinary word for an orchard came to serve as the name of a landmark. The garden at its foot, Gethsemane, was named the same practical way, after an oil press.
The Gospels return to this ridge constantly. Jesus comes over it to enter the city, sits on it to answer the disciples' questions about what is coming, walks up it after the last supper, sleeps on it during his last week, and is taken up from it in Acts. Nearly all of that happens in the phrase "the mount of the olives." Three times, twice in Luke and once in Acts, the writer instead uses the word as the hill's name, which older English Bibles print as "Olivet." The place is the same either way; only the wording changes.