en_tn/rev/09/11.md

the bottomless pit

This is an extremely deep narrow hole. Possible meanings are 1) the pit has no bottom; it continues to go down further forever or 2) the pit is so deep that it is as if it had no bottom. See how you translated this in Revelation 9:1.

Abaddon ... Apollyon

Both names mean "Destroyer." (See: rc://en/ta/man/translate/translate-names and rc://en/ta/man/translate/translate-transliterate)