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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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:
He later ordered a "thorough review of all security aspects of foreign civil aviation to Israel" in response to the incident.
From Barron's ● Oct. 9, 2026
Santa Ana Police Chief Robert Rodriguez said in a statement Sunday that his department is “conducting a thorough review of the incident, including body worn camera footage, reports, and the circumstances surrounding the arrest.”
From Los Angeles Times ● Oct. 6, 2026
Messi trusts the people who run them, some of them with him since his early days at Barcelona, and a thorough filter means he only gets offered and chooses what he is comfortable with.
From BBC ● Oct. 6, 2026
The president said he had "directed the Nigerian Air Force to immediately commence a thorough investigation into the cause of the crash to prevent future occurrences".
From Barron's ● Oct. 5, 2026
Trent Bolger was not particularly creative, but he was thorough, and subtle enough to evade detection by the enforcers of Chapel Hill High School’s Zero Tolerance Policy toward racial and ethnic slurs.
From "Darius the Great Is Not Okay" by Adib Khorram
"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 protection will largely prevent borers; if any are found in the tree I remove them with a knife and wire.
From The Apple by Various
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.
