subnormal

Definitions of subnormal
  1. adjective
    below normal or average
    “after the floods the harvests were subnormal
    Synonyms:
    abnormal, unnatural
    not normal; not typical or usual or regular or conforming to a norm
  2. noun
    a person of less than normal intelligence
    see moresee less
    type of:
    simple, simpleton
    a person lacking intelligence or common sense
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