1
as in incomplete
lacking some necessary part
a diet deficient in calcium can lead to weak bones
Synonyms & Similar Words
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Antonyms & Near Antonyms
2
as in unacceptable
falling short of a standard
woefully deficient eyesight kept him out of military service
Synonyms & Similar Words
Antonyms & Near Antonyms
3
as in lacking
not coming up to an expected measure or meeting a particular need
too deficient in common sense to be trusted to stay by himself
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Antonyms & Near Antonyms
Example Sentences
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Recent Examples of deficient
Researchers say further studies are needed to determine whether the improvements in muscle power translate into fewer falls, and whether frailer or protein-deficient seniors might see greater benefits.
—
Deirdre Bardolf, FOXNews.com, 2 Mar. 2026
Other than fiber, Americans are also deficient in vitamin D, calcium, and potassium, according to the 2020-2025 Dietary Guidelines for Americans.
—Jake Angelo, Fortune, 1 Mar. 2026
The lawsuit further contends that the current special education reimbursement rate is unconstitutionally deficient.
—ABC News, 24 Feb. 2026
Those of us who regularly eat fruits and vegetables aren’t likely to be deficient in vitamin C—natural sources of vitamin C include citrus, kiwi, strawberries, bell peppers, broccoli, and more; but liposomal vitamin C supplementation can help in certain instances.
—Brianna Peters, Vogue, 23 Feb. 2026
See All Example Sentences for deficient
Deirdre Bardolf, FOXNews.com, 2 Mar. 2026
Other than fiber, Americans are also deficient in vitamin D, calcium, and potassium, according to the 2020-2025 Dietary Guidelines for Americans.
—Jake Angelo, Fortune, 1 Mar. 2026
The lawsuit further contends that the current special education reimbursement rate is unconstitutionally deficient.
—ABC News, 24 Feb. 2026
Those of us who regularly eat fruits and vegetables aren’t likely to be deficient in vitamin C—natural sources of vitamin C include citrus, kiwi, strawberries, bell peppers, broccoli, and more; but liposomal vitamin C supplementation can help in certain instances.
—Brianna Peters, Vogue, 23 Feb. 2026
See All Example Sentences for deficient
Recent Examples of Synonyms for deficient
Adjective
-
Investigators laid out a pattern of inaccurate and incomplete campaign finance reports across several election cycles, including improper contributions falsely reported as personal loans, acceptance of improper contributions and inflated cash-on-hand numbers.—
Caitlin Yilek,
CBS News,
26 Mar. 2026
-
The precise story of how the feud began between King and the neighborhood is incomplete.—
Laura Bauer,
Kansas City Star,
26 Mar. 2026
Adjective
-
The takeover will continue until the district meets criteria set by the Texas Education Agency, which include exceeding the state and/or regional average for meeting-grade-level proficiency in reading and math, and ensuring the district has no schools unacceptable ratings for multiple years.—
Lina Ruiz,
Fort Worth Star-Telegram,
24 Mar. 2026
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To have to come and be in this particular bracket every freaking year is unacceptable.—
Scott Thompson,
FOXNews.com,
24 Mar. 2026
Adjective
-
Loro Parque, a zoo on the island of Tenerife, offers a clean and safe environment, expert care and proper mental and social stimulation that Wikie and Keijo are desperately lacking.—
Valerie Greene,
The Orlando Sentinel,
14 Mar. 2026
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Financial vulnerability in Cook County has declined modestly since 2022, with fewer households reporting having less than a week of savings and fewer lacking confidence in reaching long-term goals.—
Jennifer Tescher,
Chicago Tribune,
5 Mar. 2026
Adjective
-
As another election approaches, millions of Floridians can prove just how wrong DeSantis was.—
Steve Bousquet,
Sun Sentinel,
21 Mar. 2026
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On isolated occasions a carp has been spotted on the wrong side of the electrical barrier.—
Dinah Voyles Pulver,
USA Today,
21 Mar. 2026
Adjective
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This disparity is driven by inadequate access to prenatal care, high hypertension rates and other social factors.—
Briah Lumpkins,
Charlotte Observer,
27 Mar. 2026
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El Cerrito’s existing library is unsafe and inadequate.—
Paul Fadelli,
Mercury News,
26 Mar. 2026
Adjective
-
And that 44-point home victory was with Brandon Miller having a poor shooting night (5 of 15, 13 points).—
Scott Fowler,
Charlotte Observer,
25 Mar. 2026
-
The Dolphins’ struggles during the last decade-plus with Ross signing the checks was a result of poor leadership at the top of the football operations side.—
Omar Kelly,
Miami Herald,
24 Mar. 2026
Adjective
-
Aaron thought about writing an op-ed or speaking at a rally, but such gestures struck him as painfully insufficient.—
Oriana van Praag,
New Yorker,
28 Mar. 2026
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Kratom poisonings are probably underestimated due to the reliance on self-reports and because of insufficient testing, the study researchers and other experts agreed.—
Kristen Rogers,
CNN Money,
27 Mar. 2026
Adjective
-
This struck me as heartbreakingly lame and, therefore, as a moment of vital consequence.—
Amanda Peet,
New Yorker,
21 Mar. 2026
-
Duke fires the shot that kills the king Dying Tommy insists Duke finish him off with the bullet like a lame horse.—
Bryan Alexander,
USA Today,
20 Mar. 2026
Cite this Entry
“Deficient.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/deficient. Accessed 29 Mar. 2026.
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