Definition of superposition in US English:

superposition

noun

  • The action of placing one thing on or above another, especially so that they coincide.

    ‘the random superposition of waves of many different wavelengths’
    count noun ‘a superposition of geometric patterns’

Pronunciation

superposition

/ˌso͞oərpəˈziSH(ə)n//ˌsuərpəˈzɪʃ(ə)n/