virtual address space
Computing term: the set of virtual memory addresses that a process can use, as opposed to physical memory addresses.
Each process has its own independent virtual address space.
仮想メモリ (virtual memory) is the broader memory management technique; 仮想アドレス空間 is the address range that technique provides to a process.
multiple virtual address space
Compound of 仮想 (virtual) + アドレス (address) + 空間 (space), a direct calque of the English computing term 'virtual address space'.