"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)."
Definition borrowed from Wikipedia.
Mentioned in British Civilization: An Introduction by John Oakland (p.13).
"A Times Travel study of mainstream tour operators ' youth brochures has revealed a widespread acceptance of yobbish behaviour."
TIMES, SUNDAY TIMES (2002)