overachiever

/ˌoʊvərəˈtʃivər/
noun
  1. A person who performs better or achieves more than is expected, often by working very hard.
    • She was always an overachiever, finishing her homework days before it was due.
    • Being an overachiever can sometimes lead to stress and burnout.
    • The coach praised the team's overachiever for practicing extra hours every day.
Synonyms
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