Source : Free On-Line Dictionary of Computing

plesiochronous
     
         Nearly synchronised, a term describing a
        communication system where transmitted signals have the same
        nominal digital rate but are synchronised on different clocks.
     
        According to {ITU-T} {standards}, corresponding signals are
        plesiochronous if their significant instants occur at
        nominally the same rate, with any variation in rate being
        constrained within specified limits.
     
        [Pronunciation?  /ples'ee-oh-kroh'nus/?]
     
        (1995-03-02)