Overprinted can be substituted with various synonyms that convey a similar meaning. One possible alternative is "superimposed," which describes the act of printing something on top of an existing image or text. Another synonym for overprinted is "reimposed," which implies the repetition or reinforcement of a printed element. "Duplexed" is also a related term, typically used when printing on both sides of a sheet. Other similar words include "duplicated," "replicated," and "reproduced," all of which imply the creation of multiple copies or versions. Essentially, any term that denotes the addition of printed material over an existing print can serve as a synonym for overprinted.