Definition of deficient in English:

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Pronunciation: /dəˈfiSHənt/


1Not having enough of a specified quality or ingredient: this diet is deficient in vitamin B
More example sentences
  • The rapidly growing yearling is further jeopardized when twice daily feedings are already marginal or deficient in protein quality.
  • The summer growing season of kenaf corresponds with low quality forages deficient in protein in the Southeast.
  • I told myself that my attitude, knowledge, and skill cost a patient's life and I was deficient in all those qualities that a doctor should have.
1.1Insufficient or inadequate: they trashed the legislation as deficient
More example sentences
  • The report accuses prosecutors of conducting deficient investigations or presenting inadequate evidence at the trials.
  • She blames deficient preparation and insufficient commitment on the part of the school, but she also notes impediments in the exams themselves.
  • Similarly, she has not observed or complained about any deficient workmanship in the insulation and drywall and she believes that none exists with respect to her residence.
lacking, wanting, inadequate, insufficient, limited, poor, scant;
defective, faulty, flawed, inadequate, imperfect, shoddy, weak, inferior, unsound, substandard, second-rate, poor
2 (also mentally deficient) dated or offensive Having mental disabilities.


Late 16th century (originally in the theological phrase deficient cause, denoting a failure or deficiency that has a particular consequence): from Latin deficient- 'failing', from the verb deficere (see defect1).

Words that rhyme with deficient

coefficient, efficient, proficient, sufficient

For editors and proofreaders

Syllabification: de·fi·cient

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