'Abyss' in the Bible

And the fifth angel sounded his trumpet: and I saw a star out of the heaven fallen to the earth; and there was given to it the key of the pit of the abyss.

And it opened the pit of the abyss; and there went up smoke out of the pit as the smoke of a great furnace; and the sun and the air were darkened with the smoke of the pit.

They have a king over them, the angel of the abyss: his name in Hebrew, Abaddon, and in Greek he has for name Apollyon.

And when they shall have completed their testimony, the beast who comes up out of the abyss shall make war with them, and shall conquer them, and shall kill them:

The beast which thou sawest was, and is not, and is about to come up out of the abyss and go into destruction: and they who dwell on the earth, whose names are not written from the founding of the world in the book of life, shall wonder, seeing the beast, that it was, and is not, and shall be present.

And I saw an angel descending from the heaven, having the key of the abyss, and a great chain in his hand.

and cast him into the abyss, and shut it and sealed it over him, that he should not any more deceive the nations until the thousand years were completed; after these things he must be loosed for a little time.