n. 25B6; noun a duplicate of the invoice : COPY, carbon copy, photocopy, facsimile, mimeograph, reprint; replica, reproduction, clone; informal dupe; trademark Xerox, photostat.
25B6; adjective duplicate keys : MATCHING, identical, twin, corresponding, equivalent.
25B6; verb
she will duplicate the newsletter : COPY, photocopy, photostat, xerox, mimeograph, reproduce, replicate, reprint, run off.
a feat difficult to duplicate : REPEAT, do again, redo, replicate.