Now I am not much of a language guy, but here is something that was talked over a tea with some friends. Any new word which needs to be imported to dhivehi is taken from Arabic or Urdu. The rules are as follows if the word exists in Arabic, use it. If the word is an English word; invent a word. Example words like "terminal"; is now called "gematha" or something. Words like tragedy is taken from Arabic , I guess its called "kaarisaa" or something. Finally my view on this is ; words (bas as we call it) should not be invented or created by one person or group of 2 or 6 individuals. Or a ministry or a department. The language does not belong to the government or any organization.
Some other things to note are words like "bitu" is used by everyone for years now. But this word you will not find in the official "Radheef". But words like "saaskaf" which was invented a few years back is listed. New words which is being used include "partey"; I think this is adopted now. Other example include "salhi"; the meaning of this has changed over the years,but this is not reflect in the official books. Now I don't know much about these stuff; this is just my view. I might be wrong and very wrong. One of the recent words that I came across was "karaaseebu"; I don't know from where this came, but sounds like a nice word. I was told that this means corrupt.