self-delimiting
Computing term for a data format or encoding where the end of a unit can be determined from the data itself, without an external length field or terminator.
In a self-delimiting data format, there is no need to explicitly indicate the end of the data.
Compound of 自己 (self), 終端 (end, termination), and 判別 (discrimination, identification). The exact derivation is uncertain; it is a technical term likely coined in computing contexts.