mvmf was written at MV Communications, Inc., thus the "mv" in the name. It was originally conceived as an intelligent mail delivery agent with some advanced filtering/filing capabilities, so "mf" was for "mail functions" (or filtering or filing). Once additional related programs were contemplated, it was decided to rename the delivery agent to mvmda and make it simply one part of the mvmf package. At this point, you shouldn't think too much about the name; much like the MV in MV Communications, it doesn't really mean anything.