  We propose a new interpretation of the neutral and charged X, Z exotic hadron
resonances. Hybridized-tetraquarks are neither purely compact tetraquark states
nor bound or loosely bound molecules. The latter would require a negative or
zero binding energy whose counterpart in h-tetraquarks is a positive quantity.
The formation mechanism of this new class of hadrons is inspired by that of
Feshbach metastable states in atomic physics. The recent claim of an exotic
resonance in the Bs pi+- channel by the D0 collaboration and the negative
result presented subsequently by the LHCb collaboration are understood in this
scheme, together with a considerable portion of available data on X, Z
particles. Considerations on a state with the same quantum numbers as the
X(5568) are also made.
