To be undecided about; to lack confidence in; to disbelieve, to question.
Disbelief or uncertainty (about something); (countable) a particular instance of such disbelief or uncertainty.
The genuinity - as distinguished from the efficacity or the regularity - of a sacrament as a result of some formal dispositions being fulfilled.
The state of being valid, authentic or genuine.
State of having legal force.
A quality of a measurement indicating the degree to which the measure reflects the underlying construct, that is, whether it measures what it purports to measure (see reliability).