  Elementary keV sterile Dirac neutrinos can be a natural ingredient of the
composite neutrino scenario. For a certain class of composite neutrino
theories, these sterile neutrinos naturally have the appropriate mixing angles
to be resonantly produced warm dark matter (WDM). Alternatively, we show these
sterile neutrinos can be WDM produced by an entropy-diluted thermal freeze-out,
with the necessary entropy production arising not from an out-of-equilibrium
decay, but rather from the confinement of the composite neutrino sector,
provided there is sufficient supercooling.
