Metacognition
Etymology
Coined in the 1970s by the developmental psychologist John Flavell. It joins Greek "meta" (here meaning "about" or "beyond") with Latin "cognitio" (knowing) — a hybrid of the two classical languages. It became foundational in education and cognitive science.
noun · /met-uh-kog-NISH-un/
Thinking about your own thinking — awareness and control of your mental processes.
What it names
One of the most useful mental tools there is: the move of stepping back to monitor whether you actually understand something, why you believe it, or how you are reasoning, rather than staying inside the thought.
Example
A little metacognition during the exam saved her: she noticed she was guessing, slowed down, and reread the question.
Related idea
Where a heuristic is a shortcut you use to think, metacognition is the higher layer that watches and evaluates that thinking — and it is what the "curse of knowledge" and "Dunning–Kruger effect" both jam.