Final answer:
Pipelining is the CPU feature that allows the next instruction to be fetched before the current one has finished executing. It enhances the CPU's throughput by enabling different execution stages to work in parallel. Other unrelated terms are hyperthreading, overclocking, and multicore.
Step-by-step explanation:
The feature of a CPU that allows it to begin fetching the next instruction before it has finished executing the current one is called pipelining. This technique enables multiple instructions to overlap in execution; it divides the process of executing an instruction into separate stages and allows the CPU's different stages to work on different instructions simultaneously. Pipelining increases the CPU's throughput, the number of instructions executed per unit of time.
Hyperthreading is a technology that allows a single physical processor core to act as two logical cores to the operating system, which can help improve performance in certain multithreaded applications. Overclocking refers to the action of increasing the operating speed of a computer's CPU beyond the manufacturer's specifications. A multicore CPU is one that has several processor cores on the same chip, each of which can execute instructions independently from the others, improving performance and allowing multiple tasks to be run concurrently without as much slowdown.