Meaning of “achievement” - Learner’s Dictionary

achievement

noun uk us /əˈtʃiːvmənt/
GOOD THING [ C ]

B1 something good that you achieve:

This film is his greatest achievement to date.
SUCCESS [ U ]

success in doing something good, usually by working hard:

You get such a sense of achievement when you finish the course.

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