Quite simply means a rat that lives at the tip (tip=garbage dump in Australia). Generally used as a payout or way to describe someone who you do not like.
A sociopathic loner with a strong affection for long shorts or short longs depending on the weather. Enjoys stirring up those around him but will scurry away at first sign of conflict.
A kid that no one likes, lowest of the low. Dirty. A little smartass annoying brat that you just want to king hit. Usually a gamer, an Xbox faggot that talks shit over the mic, has a lisp and swears so much the sentence doesn’t even make sense.