The substructure of a railway, underlying the tracks; the roadbed of a railroad.
An underlying layer; a substratum.
The substance lining the bottom edge of an enclosure.
A surface on which an organism grows, or to which an organism or an item is attached.
A language that is replaced in a population by another language and that influences the language imposed on its speakers.
A surface to which a substance adheres.
A metal which is plated with another metal which has different physical properties.
A substance acted upon, as by an enzyme.
Having very slight furrows.