It's like the word "nasty" but to a much, much higher degree. For instance, small wart on someone's lip might be nasty...but someone with anal warts taking a green diareah shit in someones ear is nursty.
by Tomass W May 3, 2006
Get the nurstymug. 
Like "sick nasty" except even better and more cool. Should only be used in cases of extreme awesomeness.
Some kids, especially those who are intelligent, witty, and extraordinarly awesome, are "sick nursty"!
by D. Strunk March 27, 2007
Get the "sick nursty"mug.