a sniv is somebody who likes to run throught bushes. They like to be unoticed in large crowds of people and in some other situations. snivs like to use code words such as "sa" or "ssssssss". They like to keep to themselves and tame the bushes.
Vince: Yo Callum who is the biggest sniv in the school?
Callum: I don't know man, any ideas Nenad?
Nenad: Starts with a T ends with eo.