underachiever Edit
Noun
    a student who does not perform as well as expected or as well as the IQ indicates

Entries from Olam Open Database

Underachiever(noun)::
    പ്രതീക്ഷക്കൊത്ത്‌ ഉയരാന്‍ കഴിയാത്തവന്‍,

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