Dungtung is a word used in reference to the word "downtown".
Although it does not share any of the charateristics of the word downtown, from this word it was originated. e.g. Downtown Charlie Brown could easily be manipulated into Dungtung Chuck Brung. The word Dungtung is used basically used to gain someones attention when initial eye contact or physical attention is recognized.
If you were to see your buddy and he/she was looking hurtin from the night before because he/she was clearly drinking, you could address him/her as "Dungtung". This would indicate your recognization of what he or she must have been up to last night by the physical characteristics he/she displays. e.g. "looking pretty hurtin there Dungtung." or " Dungtung! look at you". The word is most often used with a high pitch inflection.