1825, "the art or operation of covering articles with a thin coating or film of metal;" 1833, "thin coating of one metal laid upon another," verbal noun from plate (v.).
c. 1300, "a throwing," verbal noun from cast (v.). From early 15c. as "the casting of metal, the act or process of founding;" 1788 as "a metal casting, that which has been formed by running molten metal into a mold of a desired form." Theatrical sense is from 1814. Casting couch "divan in a Hollywood casting directors office," with suggestion of sexual favors in exchange for a role in a picture is by 1948.
"to cover (something) with a layer of metal or mail," late 14c., platen, from plate (n.). Related: Plated.