Mulvoc is a package of natural language vocabulary handling code for GNUemacs. Although it could be used in a variety of ways, its original purpose is to help the user to learn vocabulary in other languages. As you use words in your emacs session, mulvoc flashes up translations of words that it has in its dictionary. It is not meant to be a translation aid or auto translator, although the author may be tempted to try to add such facilities later. Mulvoc uses a simple spreadsheet format, with a column for each language, to hold its vocabulary data.
Mulvoc reads its vocabulary from multiple files, merging the data together so that translations can be recognised even when the original and target words do not occur in the same file; for example, if you have three files each containing two languages, if file 1 gives the translation of A as B, and file 2 gives the translation of C as D, and file 3 gives the translation of B as C, mulvoc will recognise that D is a translation of A.
Mulvoc was created by John C G Sturdy, and is hosted on Sourceforge.