1. gloomy; morose; melancholy; morbid.
2. irritable; bad-tempered; splenetic.
[Origin: 1645–55; < L ātra bīli(s) black bile + -ous]
Atrabilious. Dictionary.com. Dictionary.com Unabridged (v 1.1). Random House, Inc. http://dictionary.reference.com/browse/Atrabilious (accessed: May 30, 2008).
Bob most certainly got out of bed on the wrong side this morning. He picked uninterestedly at his breakfast and cursed the other drivers on the way to work just because he didn't like the colors of their cars. He was an atrabilious grump. That settles it, he decided, next week he is going to move his collection of sharp objects away from the left side of his bed.