unregistered

/ˈʌnˌrɛdʒəstərd/

Something that isn't recorded officially is unregistered. If your car is unregistered, you can't legally drive it.

When you put something on an official list or enter it into a directory, you register it. Leaving it off such a list makes it unregistered. In some cases, this isn't a big deal — your puppy, being a lovable mixed-breed rather than a fancy purebred dog with the official paperwork to prove it, is unregistered. But when it comes to things you're required to register, like cars and guns for example, being unregistered is a real problem.

Definitions of unregistered

1. adjective

   not registered
   “an unregistered citizen”

   synonyms:

   unlisted

   not having your name entered on a voting list

   antonyms:

   registered

   listed or recorded officially

   certified, qualified

   holding appropriate documentation and officially on record as qualified to perform a specified function or practice a specified skill

   recorded

   (of securities) having the owner's name entered in a register
2. adjective

   (a boat or vessel) not furnished with official documents
   synonyms:

   undocumented

   lacking necessary documents (as for e.g. permission to live or work in a country)
3. adjective

   (of animals) not recorded with or certified by an official breed association
   “unregistered dairy cattle”

   antonyms:

   registered

   (of animals) officially recorded with or certified by a recognized breed association; especially in a stud book