凶 (Kanji for terrible)

This kanji is usually only seen by itself in fortune-telling. It's like the worst fortune or whatever, so it's frequently the punchline of jokes.

Onyomi

KYOU

In May, I fell into a terrible pit and I am still trapped there until TODAY (今日, pronounced KYOU)!!

凶悪(きょうあく) な

Heinous! ☆☆☆☆☆
凶 (terrible) + 悪 (bad) = 凶悪 ( Heinous!)

atrocious! Heinous! Some Rape of Nanking kind of shit.

大凶(だいきょう)

horrible luck ☆☆☆☆☆
大 (big) + 凶 (terrible) = 大凶 (horrible luck)

horrible luck, an atrocity.