The difference between the rank of a matrix and the number of columns it has; the dimension of the nullspace of a matrix.
A void act; a defective proceeding or one expressly declared by statute to be a nullity.
The state of being null, or void, or invalid.
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).