Strong’s Greek
G5020 — tartaroo
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
ταρταρόω
tartaroo — pronounced tar-tar-o'-o
from Tartaros (the deepest abyss of Hades); to incarcerate in eternal torment:--cast down to hell.
2 occurrences in the KJV.
2 Peter 2:4
For if God spared not the angels that sinned, but cast them down to hell, and delivered them into chains of darkness, to be reserved unto judgment;
2 Peter 2:4
For if God spared not the angels that sinned, but cast them down to hell, and delivered them into chains of darkness, to be reserved unto judgment;