It isn't well defined? I always thought a scripting language was evaluated/compiled at runtime (therefore slower, often allowing dynamically generated code to be executed, no low-level memory management like pointers), versus traditional languages which are compiled (either to assembly, or some intermediate representation, but dynamically generated code in the original language is necessarily out of the picture).

Obviously the name "scripting" comes about from the fact that such langauges are intended for "scripting" automating interaction with "objects" (application scripting, HTML scripting, shell scripting, etc.), and that high-level features and on-the-fly execution are more important than performance.

I've never met anyone who thought Python wasn't a scripting language -- I mean, you run the Python interpreter on the script file. And I've never met anyone who would call a compiled language (C, Java, etc.) a scripting language. The distinction is pretty clear to me; maybe other people can think of counterexamples?