unsupported by other evidence; used to describe an allegation where evidence cannot show or support that the allegation actually happened The plaintiff's claims were unsubstantiated.
- No additional evidence was introduced to support the unsubstantiated allegations.
- The statements were nothing more than unsubstantiated accusations.
- The rumour that the judge in the matter had a conflict of interest was unsubstantiated.
- There was an unsubstantiated report in the newspaper.
- Uncorroborated is a synonym of unsubstantiated.
- Unsubstantiated is the opposite of substantiated.