'yoboseo' is 'hello (when you answer the phone)" in korean. 'yobo is 'darling' in korean ... 'seo' is just "ending of verb' for honorific term i don't know why you ask this question here =,=;;

yo, wrongo sectiono

You mean "yobbo". Yobbo or yob is a slang term for an uncouth or thuggish working-class person. The word derives from a back slang reading of the word "boy" (boy or boyo reversed becomes yob or — slightly modified — yobbo). http://en.wikipedia.org/wiki/Yobbo The Chinese communist party are a bunch of yobbos. Yobbos like to go to football matches in England. Authoritarian governments employ yobbos to do their work.

Eliot is right. Also this word is often used in Australian English to describe uneducated men.