A "Heap Pollution" as in Non-Reifiable Types (The Java™ Tutorials > Learning the Java Language > Generics (Updated))
Why is it called that way?
Heap pollution simply implies that you have "bad stuff" in your heap. It is an analogy to (for example) water pollution which is where you have "bad stuff" in the water.
Specifically, the bad stuff here is objects of type
It is not a particularly good analogy, but it is the terminology that the Java folks coined ... and they have (in effect) defined it in the page that you linked to, and probably other places.
Why should there be? There are lots of words and phrases in use in English where nobody really knows the origin or the reasoning. (In this case, the source is known, and the reasoning are self evident ...)
Not really. It just means that nobody had previously thought to ask for a definition in a place that Google indexes. 1) The usage is restricted to the Java programming AFAIK, and 2) the analogy is obvious ... to most people who would use the term.