1. principle of superposition, superposition principle, superposition, principle, rule
usage: (geology) the principle that in a series of stratified sedimentary rocks the lowest stratum is the oldest
2. principle of superposition, Huygens' principle of superposition, principle, rule
usage: the displacement of any point due to the superposition of wave systems is equal to the sum of the displacements of the individual waves at that point; "the principle of superposition is the basis of the wave theory of light"