underachiever

/ˌʌndərəˈtʃivər/
noun
  1. A person who performs less well than expected, especially in school or work.
    • Many underachievers simply need a different learning environment to succeed.
    • He was labeled an underachiever because his test scores were far below his potential.
    • The teacher tried to motivate the underachiever by giving him extra attention.
Antonyms
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