unconclusive

Unconclusive is an adjective used to describe information, results, or arguments that do not provide a definite conclusion. In common English, it characterizes evidence or reasoning that fails to settle an issue, leaving interpretation open or the matter unresolved.

The form unconclusive is uncommon and generally considered nonstandard. The standard negation of conclusive is inconclusive, formed with the prefix in- attached to conclusive. Some early or nonstandard usages may appear with un- as a prefix, but this is not widely accepted in modern editing practice. When accuracy and clarity are required, inconclusive should be used.

In practice, inconclusive is the preferred term across science, medicine, law, journalism, and everyday discourse to indicate that evidence does not demonstrate a decisive outcome. The term can apply to data sets, study results, investigations, or arguments. For example, a clinical trial with inconclusive results does not show clear efficacy or safety; a study may have inconclusive findings if the data do not support a firm conclusion. If an author encounters an unconclusive statement, it is usually a miswording; such usage should be replaced with inconclusive or another precise descriptor such as unclear, tentative, or unresolved.