purportedly
adv. C1 Advanced US //pɝˈpɔɹtɪdˌɫi// UK //pɜːpˈɔːtɪdli// pur·port·ed·ly
adv. according to what people say or what is claimed to be true. You use this when you want to say something is true, but you are not 100% sure.
adv. according to what is claimed or reported to be the case. Often used to introduce a statement that is accepted as a premise without being proven.
The book was purportedly written by the famous author.
The report was purportedly based on secret government documents, though no evidence was ever released to the public.
The suspect was purportedly seen leaving the scene of the crime, though the witness's identification was later challenged by the defense attorney.