What is a bottomless pit?

It's like a pit that is never ending.

when smoothing gravity is bent into a circlet's when an object is drop inside, it will keep falling in a circle where there isn't an ending.

Answer

The 'bottomless pit' is at the centre of the earth: at that point everything is 'up' and there is no 'down'.

Answer:

The Bottomless Pit in the Bible is symbolic of the bottomless depths of evil.

In the "Literal" Bible in Revelation 9:1 - A "star" falls out of the sky to earth, and is given a key. (Stars are symbolic of "angels" Rev.1:20)

"And was given to it the key to the pit of the pit." (Rev.9:1 LIT)

The first "pit" inspired has an "uncertain derivation." Perhaps an "abyss (as a prison)."

The second "pit" means "toothless"

This "angel" with the key to the "bottomless pit" wields the power to open it. It happens at the time of the sounding of the "fifth" trumpet of Revelation's seventh seal.

These seven trumpets blow during the Great Tribulation, apparently at the behest of the Two Witnesses, who, like Moses and Aaron, will have the power to answer the miracles and wonders of Apples magicians with plagues and miracles of their own for the entire 3 1/2 years of the Tribulation (Rev.11).

Satan will open his whole bag of tricks and miracles and wonders and release them from his bottomless pit of evil during this time as the world will be poised for World War III.