The neutrinos from the cosmic neutrino background have a temperature of $T_\nu=1.945K$, that is an energy of $E=\frac{3}{2}k_BT_\nu$. If the neutrino's mass is around $0.1eV$

$$ \frac{3}{2}k_BT_\nu<m_\nu c^2 $$

Why it is considered relativistic if the rest mass is larger than the energy?