1.
abyss, the depths, bottomless pit
A deep, dark place or the lowest possible state. Used figuratively for situations of extreme despair, ruin, or downfall.
奈落の底に突き落とされた気分だ。
I feel like I've been thrown into the depths of an abyss.
不祥事により、会社は奈落の底へと転落した。
Due to the scandal, the company fell into ruin.
人生の絶頂から奈落の底まで落ちた経験が、彼を強くした。
The experience of falling from the peak of life to the very bottom made him stronger.
2.
below the stage, trap cellar (theater)
In traditional Japanese theater (kabuki), the space beneath the stage used for special effects, disappearances, and scene changes.
役者が奈落から舞台に上がってきた。
The actor came up onto the stage from the trap cellar.
歌舞伎座の奈落は見学できることがある。
The trap cellar of the Kabuki-za can sometimes be visited on tours.
舞台の仕掛けを動かすために、奈落では裏方のスタッフが忙しく働いている。
Backstage staff work busily in the trap cellar to operate the stage mechanisms.
奈落 originally comes from the Sanskrit word "naraka" meaning hell, borrowed into Japanese through Buddhist texts.
SENSE 1 — ABYSS:
Almost always used in the expression 奈落の底 (the bottom of the abyss). Describes extreme despair, ruin, or a disastrous fall from grace.
SENSE 2 — THEATER:
In kabuki and other traditional theater, the space beneath the stage. Actors and set pieces can be raised or lowered through trapdoors.
ETYMOLOGY:
From Sanskrit "naraka" (hell) via Buddhist terminology. The kanji are ateji (phonetic characters chosen for their readings, not meanings).