substratum
language that has lower power or prestige than another. Both substratum and superstratum languages influence each other, but in different ways
en-GB/ˌsʌbˈstɹɑːtəm/
en-US/səbˈstɹeɪdəm/
language that has lower power or prestige than another. Both substratum and superstratum languages influence each other, but in different ways