What is "eocambrian"

Eocambrian is a loosely used, imprecisely defined term referring to the latest (youngest) portion of time in the Precambrian Eon or to the uppermost Precambrian sediments which were continuously deposited across the Precambrian- Cambrian time boundary.

While the term had some usage in older literature, it does not appear on the official ICS time scale nor in the AGI Glossary of Geology.