Unkempt literally means “not combed,” but use it to describe anything with a sloppy appearance. Your hair probably looks unkempt when you roll out of bed in the morning. Keep it that way if you're going for the rock star look.
From the fusing of un- “not” with kempt “neat” comes the adjective unkempt. Kempt has fallen out of use, but unkempt persists as a popular word to describe anything unpolished, rough, or disorderly. Pig sties, the corrals where pigs live, are usually quite unkempt. That's why your mom keeps calling your messy, unkempt train wreck of a room a pig sty.