S: (n) principle, rule (a rule or law concerning a natural phenomenon or the function of a complex system) "the principle of the conservation of mass"; "the principle of jet propulsion"; "the right-hand rule for inductive fields"
S: (n) superposition ((geometry) the placement of one object ideally in the position of another one in order to show that the two coincide)
S: (n) superposition (the placement of one thing on top of another)
S: (n) stratification (the placing of seeds in damp sand or sawdust or peat moss in order to preserve them or promote germination)
S: (n) juxtaposition, apposition, collocation (the act of positioning close together (or side by side)) "it is the result of the juxtaposition of contrasting colors"