unjoinable
/ʌnˈdʒɔɪnəbəl/Definitions
1. adjective
Impossible to join or connect; unable to be united or associated.
“The unjoinable fragments of the broken vase made it difficult to repair.”
2. noun
A person or thing that cannot be joined or connected; something that is unable to be united or associated.
“The unjoinable pieces of the puzzle made it impossible to complete.”