Singlet-Doublet Fermion Origin of Dark Matter, Neutrino Mass and W-Mass
  Anomaly
  Motivated by the recently reported anomaly in W boson mass by the CDF
collaboration with $7\sigma$ statistical significance, we consider a
singlet-doublet (SD) Majorana fermion dark matter (DM) model where the required
correction to W boson mass arises from radiative corrections induced by SD
fermions. While a single generation of SD fermions, odd under an unbroken $Z_2$
symmetry, can not explain the W boson mass anomaly while being consistent with
DM phenomenology, two generations of SD fermions can do so with the heavier
generation playing the dominant role in W-mass correction and lighter
generation playing the role in DM phenomenology. Additionally, such multiple
generations of SD fermions can also generate light neutrino masses radiatively
if a $Z_2$-odd singlet scalar is included.
