We resort to the concepts of realism and indefiniteness introduced in Ref. [40], and based on the exploitation of ideal quantum tomography procedures. These concepts are connected to the existence of nonlocal correlations, and moreover allow to introduce a measure of nonlocality. In this paper we apply and test the approach of Ref. [40] in the physically relevant phenomenon of two-flavor neutrino oscillations, both in the plane-wave approximation and in the wave-packet approach, finding meaningful confirmations of the validity of the methodology, which allows to discriminate among distinct characters of different observables, and consequently on their physical relevance.