Refers to serious misfortune, disaster, or evil befalling someone. Often used in a somewhat formal or literary context.
彼は人生で多くの厄難に遭った。
He encountered many calamities in his life.
このお守りは厄難から守ってくれると言われている。
This amulet is said to protect you from misfortune.
Compound of 厄 (calamity, misfortune) and 難 (difficulty, hardship). The exact historical derivation is uncertain, but the combination naturally conveys serious trouble or disaster.