Disbelief or uncertainty (about something); (countable) a particular instance of such disbelief or uncertainty.
To be undecided about; to lack confidence in; to disbelieve, to question.
the belief of something based upon reasonable evidence, or upon something known to be true
the condition upon which something is presumed
the act of presuming, or something presumed
An inference that a trier of fact is either permitted or required to draw under certain factual circumstances (as prescribed by statute or case law) unless the party against whom the inference is drawn is able to rebut it with admissible, competent evidence.