By Allegation is a phrase used to indicate that something is being claimed or stated as true, but may not be confirmed or proven. Synonyms for this phrase include purportedly, supposedly, and allegedly. All of these words convey the notion that something is believed to be true, but there could be doubt or uncertainty around the veracity of the claim. Other synonyms for By Allegation include reportedly, hypothetically, and speculatively. Essentially, all of these words serve to introduce a statement that is not necessarily factual and may require more investigation or evidence to confirm or refute.