I was reading a patent yesterday and ran into the term "Bunte salt". I wasn't familar with the term, and from the context, it wasn't apparent what the term meant. The IUPAC Gold Book quickly clarified what a Bunte salt is, and also why I shouldn't have felt bad for my ignorance - they have declared the term is obsolete and its use, as of 1997, is discouraged. 
 What a wishy-washy position to take! It is obsolete, but its use is discouraged. Dictionaries and grammar guides have to make a choice. They can either be descriptive (describing how people use a language without making judgments about it's "correctness") or they can be prescriptive (describing the correct way that a language should be used). Here, IUPAC is doing both.
 I'm using the term industrial practitioners as the vast majority of patents are written by them. I do acknowledge the existence (the ever growing existence at that) of university patents, but they still are an extremely small percentage of what is applied for and issued.