return frame

The saved snapshot of a thread's state that the CPU restores to resume it exactly where it left off.

When an interrupt or exception pauses a thread, the CPU stores its registers and position as a structured block on the stack — the return frame — so it can pick up precisely where it stopped. Resuming means popping this frame back into the processor. If the frame is malformed or inconsistent, the thread returns into a broken state, which is a common source of subtle crashes.