assiduous

adjective

as·​sid·​u·​ous ə-ˈsij-wəs How to pronounce assiduous (audio)
-ˈsi-jə-
: showing great care, attention, and effort : marked by careful unremitting attention or persistent application
assiduous planning
an assiduous book collector
She tended her garden with assiduous attention.
assiduously adverb
assiduousness noun

Did you know?

While assiduous means “showing great care, attention, and effort,” and in some situations may be an appropriate substitute for careful, it’s got a bit more oomph than careful in that it suggests a dogged or tireless persistence. If you are assiduous in your efforts (or work, research, analysis, training, preparations, etc.) for example, it’s implied that you’re in it for the long haul, or that you have the ability to “sit with” a task or challenge for a considerable amount of time. This makes sense given that assiduous comes from the Latin verb assidēre, meaning “to sit beside.”

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The History of Assiduous

Assiduous came to English directly from the Latin assiduus, an adjective derived from the verb assidēre "to sit beside." To the ancient Romans, assiduus carried meanings ranging from “settled or rooted in place” to “constantly present” to “persistent, unremitting." This last sense was the one borrowed into English four hundred years ago and still used today, often in complimentary phrases such as "an assiduous student" and “assiduous efforts.” In the 18th century, the word took on a mildly pejorative meaning, "exhibiting a fawning attentiveness; obsequious," when used of someone striving to please. This sense has largely passed out of use.

Choose the Right Synonym for assiduous

busy, industrious, diligent, assiduous, sedulous mean actively engaged or occupied.

busy chiefly stresses activity as opposed to idleness or leisure.

too busy to spend time with the children

industrious implies characteristic or habitual devotion to work.

industrious employees

diligent suggests earnest application to some specific object or pursuit.

very diligent in her pursuit of a degree

assiduous stresses careful and unremitting application.

assiduous practice

sedulous implies painstaking and persevering application.

a sedulous investigation of the murder

Examples of assiduous in a Sentence

They were assiduous in their search for all the latest facts and figures. The project required some assiduous planning.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The corruption alleged is less eye-popping than assiduous. The Editors, National Review, 27 Sep. 2024 In this new era, Russia and China represent neither chess pieces to be moved through assiduous acts of wise statesmanship nor great-power challengers that can be handled effectively without American activism. Richard Fontaine, Foreign Affairs, 18 Nov. 2022 In recent years, Portland has become a byword for fashionable left-wing guff, including the notion that crime and homelessness are little more than voluntary social constructs that are better fought with kind words and substantial welfare spending than with the assiduous enforcement of the law. The Editors, National Review, 23 May 2024 The irony of the term extension is that Disney, which pushed so hard to keep its own creations out of the public domain, is perhaps our most assiduous exploiter of, yes, the public domain. Michael Hiltzik, Los Angeles Times, 26 Dec. 2023 See all Example Sentences for assiduous 

Word History

Etymology

Latin assiduus, from assidēre to sit beside

First Known Use

circa 1552, in the meaning defined above

Time Traveler
The first known use of assiduous was circa 1552

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Dictionary Entries Near assiduous

Cite this Entry

“Assiduous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/assiduous. Accessed 23 Nov. 2024.

Kids Definition

assiduous

adjective
as·​sid·​u·​ous ə-ˈsij-(ə-)wəs How to pronounce assiduous (audio)
: constantly attentive : diligent
assiduity
ˌas-ə-ˈd(y)ü-ət-ē
noun
assiduously adverb
assiduousness noun

More from Merriam-Webster on assiduous

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