Source : Free On-Line Dictionary of Computing

microfloppies
     
        3.5-inch floppies, as opposed to 5.25-inch {vanilla} or
        mini-floppies and the now-obsolete 8-inch variety.  This term
        may be headed for obsolescence as 5.25-inchers pass out of
        use, only to be revived if anybody floats a sub-3-inch floppy
        standard.  See {stiffy}, {minifloppies}.
     
        [{Jargon File}]