Only unkempt musicians can participate in the West by Southwest music festival. That is the rule.
Not combed: unkempt hair.
Not properly maintained; disorderly or untidy: an unkempt garden. See Synonyms at sloppy.
//-->[Middle English unkemd : un-, not; see un-1 + kembed, past participle of kemben, to comb (from Old English cemban; see gembh- in Indo-European roots).]
( American Heritage)