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Synonyms

diligent

American  
[dil-i-juhnt] / ˈdɪl ɪ dʒənt /

adjective

  1. constant in effort to accomplish something; attentive and persistent in doing anything.

    a diligent student.

    Synonyms:
    sedulous, assiduous, industrious
  2. done or pursued with persevering attention; painstaking.

    a diligent search of the files.

    Synonyms:
    unremitting, tireless, indefatigable

diligent British  
/ ˈdɪlɪdʒənt /

adjective

  1. careful and persevering in carrying out tasks or duties

  2. carried out with care and perseverance

    diligent work

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Synonym Usage

See busy.

Other Word Forms

Etymology

Origin of diligent

First recorded in 1300–50; Middle English, from Anglo-French or directly from Latin dīligent- (stem of dīligēns ), present participle of dīligere “to choose, like,” equivalent to dī- di- 2 + -ligere (combining form of legere “to choose, read”); see -ent

Compare meaning

How does diligent compare to similar and commonly confused words? Explore the most common comparisons:

Explanation

Someone who is diligent works hard and carefully. If you want to write the epic history of your family, you'll have to be very diligent in tracking down and interviewing all of your relatives. Diligent comes from the Latin diligere, which means "to value highly, take delight in," but in English it has always meant careful and hard-working. If you're a diligent worker, you don't just bang away at your job; you earnestly try to do everything right. Although being lucky and talented doesn't hurt, it's the diligent person who eventually succeeds.

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Vocabulary lists containing diligent

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“Even the most diligent and responsible pet owner can experience the unexpected,” Oreck said.

From Los Angeles Times • Jul. 3, 2026

Your best plan may be a combination of existing U.S. retirement accounts, taxable brokerage investing and diligent saving.

From MarketWatch • Jul. 2, 2026

"Luckily the keepers here are incredibly diligent, so they are noticing the subtle changes in an animal."

From BBC • Apr. 21, 2026

Avoiding price increases for consumers will require diligent utility commissioners who scrutinize spending plans and push for the grid to be used more efficiently, he said.

From The Wall Street Journal • Apr. 14, 2026

I had made a hurried but diligent search which I finally abandoned, telling myself I’d be back for it later.

From "The Secret History" by Donna Tartt

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