a substance or layer which underlies something, or on which some process occurs, in particular
底层,下层;衬托物,尤指:
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。
the substance on which an enzyme acts
底物,酶作用物。
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。
"early 19th cent.: Anglicized form of