title_body: How do you call a "stillborn language"?
upvoted_answer: You're describing a couple different and not totally related things with different terminology used for each: 
  
  
  Classical Latin is an example of a literary language, a language used not really in speech but used to communicate through writing.
  Modern Standard Arabic, one of those artificial languages based off of a natural one but not really being a spoken language. It's very frequently affected by diglossia, and not really used in natural settings. It's usually referred to as simply a standardized lanuage, and also qualifies as a literary language.
  Hebrew as spoken in daily life in Israel would qualify as the first type you described, a modernized version of an old language that was resurrected after death. It would be referred to as a revived language.