thorough
adjective
executed without negligence or omissions.
thorough
American
[thur-oh, thuhr-oh]
/ ˈθɜr oʊ, ˈθʌr oʊ /
adjective
-
executed without negligence or omissions.
a thorough search.
- Synonyms:
- total, unqualified, sheer, downright, exhaustive, in-depth
- Antonyms:
- superficial, partial
-
thorough enjoyment.
-
extremely attentive to accuracy and detail; painstaking: a thorough analysis.
a thorough worker;
a thorough analysis.
-
having full command or mastery of an art, talent, etc..
a thorough actress.
-
extending or passing through.
adverb
noun
thorough
1
British
/ ˈθʌrə /
adjective
-
carried out completely and carefully
a thorough search
-
(prenominal) utter
a thorough bore
-
painstakingly careful
my work is thorough
Thorough
2
British
/ ˈθʌrə /
noun
Other Word Forms
Etymology
Origin of thorough
First recorded before 900; Middle English (preposition and adverb); Old English thuruh, variant of thurh through
Explanation
Thorough describes something that is painstakingly complete, like a thorough search for your missing keys in which you look for them in coat pockets, under the table, in the refrigerator — in every single place you can think of. Thorough rhymes with "burrow": "THUR-oh." It looks a lot like through but remember thorough is an adjective, so you might use it to describe a thorough investigation or a thorough review. In contrast through is used most often as a preposition — you might look through every drawer, for example, in a search — or as an adverb — you might see a hole in your pocket where coins fall through.
Vocabulary lists containing thorough
"Earth and Space"
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Harry Potter and the Prisoner of Azkaban
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Everything, Everything
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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.
See Examples For:
Ince suggests doing thorough research to find the right fit for you, and cautions against using online resources which may offer generic advice.
From BBC ● Aug. 8, 2026
A thorough rethinking of Vatican ecumenical strategy toward the Christian East is essential.
From The Wall Street Journal ● Aug. 6, 2026
"Even relatively small exporters and shipments are subject to thorough review and scrutiny on both sides of the globe, and any diverted products would have no service, support, or updates."
From Barron's ● Jul. 28, 2026
“We are committed to conducting a thorough investigation, holding those responsible accountable and standing with our Jewish community, all faith communities and every resident against all forms of hatred and intolerance.”
From Los Angeles Times ● Jul. 25, 2026
To attempt any such procedure without thorough advance research on the hazards involved would be the height of irresponsibility.
From "Silent Spring" by Rachel Carson
"Thorough culling" to reduce the number of bears is the only effective way to reduce the risk for local people, researcher Ohnishi said.
From Barron's ● Nov. 8, 2025
Thorough clinical trials have already proven benefits to heart health - and nausea is a known side-effect - but other findings will need to go through similar rigorous testing.
From BBC ● Jan. 20, 2025
Thorough background checks have long been a norm used by incoming presidents when choosing their Cabinet.
From Salon ● Nov. 25, 2024
Thorough research might also speed assistance to thousands of Americans who say they were injured.
From New York Times ● May 3, 2024
"Thorough and reliable, and just such a work as is greatly needed."
From Lectures on the true, the beautiful and the good by Victor Cousin
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
