'Dragon's' in the Bible

So I went out during the night through the Valley Gate toward Dragon's Well, and from there to the Dung Gate, inspecting the walls of Jerusalem that were broken down and burned by fire.

Now the dragon's tail swept away a third of the stars in heaven and hurled them to the earth. Then the dragon stood before the woman who was about to give birth, so that he might devour her child as soon as it was born.

Then I saw three unclean spirits like frogs coming from the dragon’s mouth, from the beast’s mouth, and from the mouth of the false prophet.