Pronunciation: (sOO'pur-strā"tum,--strat"um),[key] —n., —pl.-stra•taPronunciation: (-strā"tu,--strat"u),[key]-stra•tums. 1. an overlying stratum or layer.
2. Historical Ling.a set of features of a language traceable to the influence of a language formerly spoken within the same society by a dominant group: English has a Norman-French superstratum. Cf. substratum.