assiduous

adjective
as·​sid·​u·​ous | \ə-ˈsij-wəs, -ˈsi-jə-\

Definition of assiduous 

: 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.

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Other Words from assiduous

assiduously adverb
assiduousness noun

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

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, "obsequious," when used of someone striving to please. This sense has largely passed out of use.

Did You Know?

Judges presiding over assizes (former periodical sessions of the superior courts in English counties) had to be assiduous in assessing how to best address their cases. Not only were their efforts invaluable, but they also served as a fine demonstration of the etymologies of "assiduous," "assess," and "assize." All three of those words derive from the Latin verb assidēre, which is variously translated as "to sit beside," "to take care of," or "to assist in the office of a judge." "Assidēre," in turn, is a composite of the prefix ad- (in this case, meaning "near" or "adjacent to") and sedēre, meaning "to sit."

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

Her academic approach to collecting is reinforced by her assiduous inventories of each object’s provenance. Luzanne Otte, Town & Country, "A Day in the Life of Southern Charm's Patricia Altschul," 12 July 2018 This means that the assiduous use of insect repellent as well as frequent tick checks will make a huge difference in preventing disease. Dipesh Navsaria, Houston Chronicle, "What parents should know to prevent — and deal with — bug bites," 6 July 2018 But an overly assiduous car could also make human drivers frustrated. Aarian Marshall, WIRED, "False Positives: Self-Driving Cars and the Agony of Knowing What Matters," 29 May 2018 After about a century of assiduous dam-building, the United States has gotten out of the construction business and moved to dam-removal. Michael Hiltzik, latimes.com, "This zombie dam project underscores California's dilemma over water," 16 May 2018 The ceremony Monday was covered in assiduous detail on state television. Jim Heintz, chicagotribune.com, "Russian President Vladimir Putin sworn in for 4th term, promises economic reforms," 7 May 2018 Though an infrequent churchgoer himself, Trump devotes assiduous attention to the political interests of religious adherents. Andrew Malcolm, San Francisco Chronicle, "GOP-leaning religious believers overlook Trump’s moral lapses," 26 Apr. 2018 In the meantime, Geelhood and Klotz maintained their assiduous vigil. Jennifer Kahn, New York Times, "Should Some Species Be Allowed to Die Out?," 13 Mar. 2018 Besides, Mr Moon is an assiduous supporter of UN sanctions. The Economist, "BanyanDetente on the Korean peninsula is a relief," 15 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'assiduous.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of assiduous

circa 1552, in the meaning defined above

History and Etymology for assiduous

Latin assiduus, from assidēre to sit beside

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Statistics for assiduous

Last Updated

13 Nov 2018

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Time Traveler for assiduous

The first known use of assiduous was circa 1552

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More Definitions for assiduous

assiduous

adjective
as·​sid·​u·​ous | \ə-ˈsi-jə-wəs \

Kids Definition of assiduous

: showing great care, attention, and effort They were assiduous in gathering evidence.

Other Words from assiduous

assiduously adverb

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Comments on assiduous

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