Meaning of “correction” - Learner’s Dictionary

correction

noun [ C, U ] us uk /kəˈrekʃən/
I gave her essay back to her with very few corrections.Every time I get an essay back there are fewer corrections.He handed my essay back to me with a mass of corrections.You can see where she's made corrections to the manuscript.He was cross with himself because he had so many corrections in his latest piece of work.

B1 a change to make something right or better, or the act of making such a change:

She made / some corrections before handing in the essay.

(Definition of “correction” from the Cambridge Learner’s Dictionary © Cambridge University Press)