Deficient means not enough or not adequate. Maybe you were deficient in caffeine that day. Maybe you were lacking in study time. But no doubt about it: you came up with a deficient number of correct answers on the physics test.

If your new car fund remains deficient, you don't have enough money to buy a new car. This presents a problem if your current car is deficient in some way — say, it no longer has enough engine power to drive up a hill. You may not feel you have what it takes to get a job, but the reality is you will have to choose between indulging your own deficiencies in this area or the car's.

Definitions of deficient
  1. adjective
    inadequate in amount or degree
    “a deficient education”
    deficient in common sense”
    synonyms: lacking, wanting
    inadequate, unequal
    lacking the requisite qualities or resources to meet a task
  2. adjective
    of a quantity not able to fulfill a need or requirement
    synonyms: insufficient
    meager, meagerly, meagre, scrimpy, stingy
    deficient in amount or quality or extent
    depleted, low
    no longer sufficient
    inadequate, poor, short
    not sufficient to meet a need
    lean, skimpy
    containing little excess
    light, scant, short
    less than the correct or legal or full amount often deliberately so
    see moresee less
    of a quantity that can fulfill a need or requirement but without being abundant
    more than enough in size or scope or capacity
    adequate, decent, enough
    sufficient for the purpose
    sufficient to provide comfort
    show more antonyms...
  3. adjective
    falling short of some prescribed norm
    synonyms: inferior, substandard
    varying from or not adhering to a standard
Word Family

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