Strongs: G5421
G5421 @ φρέαρ phrear freh'-ar Of uncertain derivation; a hole in the ground (dug for obtaining or holding water or other purposes) that is a cistern or well; figuratively an abyss (as a prison): - well pit.
Luke:14:5
John:4:11
John:4:12
Revelation:9:1
Revelation:9:2