To clear all definitions or to reclaim resources used by the kernel, you may want to restart it.
Using the Menu...
Quit the kernel
Quit the kernel by choosing Evaluation ▶ Quit Kernel ▶ "kernel name", where “kernel name” is typically “Local”:
Restart the kernel
Any subsequent evaluation will automatically restart the kernel:
Programmatically...
Quit the kernel
Quit the kernel by evaluating Quit:
Restart the kernel
Any subsequent evaluation will automatically restart the kernel:
Using the Menu...
Quit the kernel
Restart the kernel
Any subsequent evaluation will automatically restart the kernel:
Programmatically...
Quit the kernel
Quit the kernel by evaluating Quit:
Restart the kernel
Any subsequent evaluation will automatically restart the kernel: