excruciating

(verb) torment emotionally or mentally. Synonyms: torment, torture, excruciate, rack.

(verb) subject to torture. Synonyms: torture, excruciate, torment. Examples: "The sinners will be tormented in hell, according to the bible."

(adj) extremely painful. Synonyms: agonizing, agonising, harrowing, torturing, torturous, torturesome.