GrassmannParity is a data type.
GrassmannParity
E.g. DataType[F, GrassmannParity] = 1 declares F to be of bosonic type and DataType[F, GrassmannParity] = -1 of fermionic one.
DataType[F, GrassmannParity] = 1
F
DataType[F, GrassmannParity] = -1
Overview, DataType.