olemus
Wiktionary:
noun
1. one that resembles or corresponds to another; an identical copy
2. (law) an original instrument repeated; a document which is the same as another in all essential particulars, and differing from a mere copy in having all the validity of an original

näiteid
duplicate cheque -- tšeki dublikaat
duplicate copy -- dublikaat, teine eksemplar
duplicate of exchange -- veksli dublikaat
duplicate receipt-- topeltkviitung
receipt in duplicate -- kviitung kahes eksemplaris