. In the former sense, the abbreviation is lossless, while in the latter sense it is lossy. Compression permits either or both kinds, and so its effects are not always exactly reversible. [Computer and Information Sciences] 
 [diplomatics] A brief formula expressing respect, such as "sincerely yours" or "yours truly". [Archives] 
n., An exact copy of a document on which has been written explanations of things that could not or were not copied; e.g., written signature might be replaced on conformed copy with