A greeting. Drunken email from employee to employer regarding failure to show up for work resulted in the query "ko?" instead of "ok?" Time has eroded the original meaning to a greeting, after months of harrassment insued where the entire workplace greeted the unfortunate employee with "ko!" every morning.
KO! How are you this AM?
Adjective: Ultra Cool, Slick
Man that is a pretty saftey motorcycle you have there!