  Neutrino decay in the minimal seesaw model containing three right handed
neutrinos and a complex $SU(2)\times U(1)$ singlet Higgs in addition to the
standard model fields is considered. A global horizontal symmetry $U(1)_H$ is
imposed, which on spontaneous breaking gives rise to a Goldstone boson. This
symmetry is chosen in a way that makes a) the contribution of heavy ($\leq$
  MeV) majorana neutrinos to the neutrinoless double beta decay amplitude
vanish and b) allows the heavy neutrino to decay to a lighter neutrino and the
Goldstone boson. It is shown that this decay can occur at a rate much faster
than in the original Majoron model even if one does not introduce any
additional Higgs fields as is done in the literature. Possibility of describing
the 17 keV neutrino in this minimal seesaw model is investigated. While most of
the cosmological and astrophysical constraints on the 17 keV neutrino can be
satisfied in this model, the laboratory limits coming from the neutrino
oscillations cannot be easily met. An extension which removes this inadequacy
and offers a consistent description of the 17 keV neutrino is discussed.
