\nVDashThe symbol \nVDash is used in mathematical logic to denote that a certain statement or formula does not semantically entail another. It is the negation of the \VDash symbol, which represents semantic entailment. In other words, if A \nVDash B, it means that A does not entail B.
Statement A does not semantically entail statement B.
A \nVDash BThe set of statements \Gamma does not entail the statement \phi.
\Gamma \nVDash \phiThe predicate P(x) does not entail the predicate Q(x).
P(x) \nVDash Q(x)