substrate
/ˈsʌbstreɪt/noun
1- a substance or layer which underlies something, or on which some process occurs, in particular底层, 下层; 衬托物, 尤指：
1.1
- the surface or material on or from which an organism lives, grows, or obtains its nourishment底土（层）; 培养基; 基质; 基层。
1.2
- the substance on which an enzyme acts底物, 酶作用物。
1.3
- a material which provides the surface on which something is deposited or inscribed, for example the silicon wafer used to manufacture integrated circuits.（供放置或刻的）底面。
词源
early 19th cent.: Anglicized form of SUBSTRATUM.