Why are generic drug names so weird?

Ever wonder why generic drugs had such bizarre names, like "natalizumab?" I did and I finally found some rationale behind it.

Here are a few good sites that give some explanation.

For example, the "mab" in "natalizumab" (Tysabri) means it is a mono-clonal antibody (the type of protein it is), the "zu" means it was humanized (made to look like a human antibody rather than mouse or other animal from which it was developed) and the "li" means it targets the immune system.

Exercise for the reader: rituximab.