sourceless

/ˈsɔrsləs/
adjective
  1. Without a known origin, source, or cause.
    • The anonymous tip was sourceless, making it hard to verify.
    • A sourceless river appears suddenly from underground springs.
    • The rumor was sourceless, so nobody knew if it was true.
What does "sourceless" mean? | whatsthatwordmean | whatsthatwordmean