substratum
🇺🇸
/ˈsʌbstreɪtəm/
🇬🇧
/ˈsʌbstrɑːtəm/
noun
R
a layer under another layer, usually used to talk about earth or rock
The workers discovered an ancient substratum of stone while digging.
工人们挖掘时发现了一个古老的石头底层。
translation
底层
词形变化
Plural
substrata