The name tribimaximal reflects the commonality of the tribimaximal mixing matrix with two previously proposed specific forms for the PMNS matrix, the trimaximal and bimaximal mixing schemes, both now ruled out by data. In tribimaximal mixing, the ν ν 2 neutrino mass eigenstate is said to be "trimaximally mixed" in that it consists of a uniform admixture of ν ν e , ν ν μ μ and ν ν τ τ flavour eigenstates, i.e. maximal mixing among all three flavour states. The ν ν 3 neutrino mass eigenstate, on the other hand, is "bimaximally mixed" in that it comprises a uniform admixture of only two flavour components, i.e. ν ν μ μ and ν ν τ τ maximal mixing, with effective decoupling of the ν ν e from the ν ν 3 , just as in the original bimaximal scheme.