Adjective
plesiochronous (not comparable)
(communication) Almost, but not quite, synchronous.
The DS-3 standard uses bit stuffing to allow the clocks of its tributaries to be plesiochronous.
The method was developed to replace the plesiochronous digital hierarchy (PDH) system for transporting large amounts of telephone calls and data traffic over the same fiber without synchronization problems. Source: Internet
Plesiochronous synchronization As far as synchronization is concerned, the multiplexing of plesiochronous signals is not completely trouble free, especially when it comes to demultiplexing the circuits. Source: Internet
The plesiochronous digital hierarchy Based on the E1 signal, the ITU defined a hierarchy of plesiochronous signals that enables signals to be transported at rates of up to 140 Mbit/s. Source: Internet