An assertion, especially an accusation, not necessarily based on facts. (noun)
Examples of word allegation
The term allegation implies just that, alleged, an unproved assertion.
"I can reassure the British public that we are very careful in who we fund and this allegation is a very rare one for us but one that causes a great deal of concern."
Bart: To start, I would love to see the actual transcript of that oral argument to see if this allegation is accurate.