This uncommon term is used to describe the act of dividing a thing into eight sections, called octants; colloquially, "pieces of eight." I Ching lends itself well to illustrating the notion since it can be octo-partitioned twice in succession as the following graphic depicts.
The largest cube represents I Ching as a holism. The mid-sized cube represents Ba Gua (one of the Eight Diagrams), a three-line figure or trigram, two of which, when arranged in superposition, produce an hexagram. The smallest cube, its six faces standing for the six lines, represents an individual hexagram out of the 64 that comprise the I Ching.