evidentially

Evidentially is an English adverb formed from evidential, meaning relating to evidence or to the evidence supporting a claim. It is used to indicate that a statement or conclusion rests on evidence, testimony, or reported information rather than on direct observation. In ordinary speech, evidentially is uncommon; it is more often found in academic, analytic, or linguistics contexts where writers discuss how knowledge is obtained and presented.

Within linguistics, evidentiality is a cross-linguistic category describing how information is sourced: directly observed, reported, inferred, or assumed. Many languages mark evidentiality through verbal affixes or particles. English typically encodes evidential stance with phrases such as according to..., reportedly, supposedly, or based on the data, rather than with a dedicated grammatical marker. The adverb evidentially can function to label a statement as grounded in evidence, though its use can be stylistically marked and potentially awkward outside formal writing.

Usage notes: because evidentially is rare and somewhat specialized, writers often prefer phrases that clearly signal the evidential source, such as "based on the evidence," "as reported by," or "according to the study."

Related concepts include evidentiality and evidential markers.