Origins of Tartarus
The verb ‘ταρταρόω’ sounds rather incongruous with the Bible and turns the reader only in one direction – to Greek mythology. I would like to quickly sketch the myth in which ‘Tartarus’ is mentioned.
The very first time this word appears is Hesiod’s Theogony. It is a poetic attempt to collect and synchronize Greek myths that were circulating in Greece. At the very beginning of the Hesiod’s work we find out that Titans were the offspring of Gaia and Uranus, Greek gods that represent heaven and earth. It can be interpreted, I assume, that they were children of heaven and earth, a common motif in ancient mythologies. There were plenty of Titans, they had brothers and sisters, and also there were generations of them. Suddenly the wrath of Uranus burst out against them because he was scared of them and he planned to put them in Tartar. Yet Gaia tricked him with the help of Cronos and Uranus was defeated. From his blood giants were born. Uranus forewarned Cronos that he will also be defeated by one of his children, so he began eating all of them. That happened until his wife, Reia, gave him a stone to eat instead of Zeus. When Zeus matured he fought with Cronos and the Titans:
Cottus and Briareos and Gyes insatiate for war raised fierce fighting: three hundred rocks, one upon another, they launched from their strong hands and overshadowed the Titans with their missiles. (Theogony 713-715)
The Titans were cast into Tartarus which was located beneath the earth and even hades, in the deepest part of the world.
[Cottus and Briareos and Gyes] buried them beneath the wide-pathed earth, and bound them in bitter chains when they had conquered them by their strength for all their great spirit, as far beneath the earth to Tartarus. For a brazen anvil falling down from heaven nine nights and days would reach the earth upon the tenth: and again, a brazen anvil falling from earth nine nights and days would reach Tartarus upon the tenth. (Theogony 716-725)
The word ταρταρόω appears also in Homer’s Odyssey and it describes Tartarus in a similar way:
Murky Tartarus, far, far away, where is the deepest gulf beneath the earth, the gates whereof are of iron and the threshold of bronze, as far beneath Hades as heaven is above earth: then shall ye know how far the mightiest am I of all gods. (Illiad 8:14-16)
Tartarus, the murky dungeon beneath the ground where the Titans (and other semi-divine beings) are kept. Is it the realm to which 2 Peter refers? Obviously yes, as can be seen by the linking word, similar way of describing it and purpose of the place.