What Does Parent Partition Mean?
A parent partition is an instance of partition within the Windows Hyper V virtualization environment that is responsible for running the virtualization stack and creating child partitions. The parent partition is the second layer of partition after the root partition. It directly interfaces with hardware and logical virtualization resources.
Techopedia Explains Parent Partition
A parent partition primarily provides a logically isolated space for executing the hypervisor's virtualization-specific processes. The parent partition has its own share of storage, memory and computing resources. Each instance of a Hyper V virtualization environment can have only one parent partition. It interfaces the primary hypervisor component stored in the root partition using the hypercall API to create one or more child partitions.
A parent partition is generally considered the root partition; however, parent partitions are logically distributed partitions for hypervisor-specific operations.