thorough

1 of 3

adjective

thor·​ough ˈthər-(ˌ)ō How to pronounce thorough (audio)
 sometimes  ˈthȯr-;
ˈthə-(ˌ)rō
Synonyms of thoroughnext
1
: carried through to completion : exhaustive
a thorough search
2
a
: marked by full detail
a thorough description
b
: careful about detail : painstaking
a thorough scholar
c
: complete in all respects
thorough pleasure
d
: having full mastery (as of an art)
a thorough musician
thoroughness noun

thorough

2 of 3

preposition

archaic
: through

thorough

3 of 3

adverb

archaic
: through

Synonyms

Adjective

See All Synonyms & Antonyms in Thesaurus

Examples of thorough in a Sentence

Adjective … one realized that it was the restaurant's thorough and even comic Frenchness that had made it so entirely New York. — Adam Gopnik, New Yorker, 22 Mar. 2004
Bruce tells me to squat down and Koani sidles up, ears flattened, tail tucked away, and gives my face a thorough licking. — Nicholas Evans, Daily Telegraph, 26 Sept. 1998
The job was uncharacteristically thorough for a Russian contract killing—three different types of bullets riddled Mikho's body. — New Republic, 15 Dec. 1997
a thorough understanding of the rules and regulations The investigator will have to be thorough.
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.
Adjective
Image Some senior Israeli officials have argued that there will never be a better moment to take out the major nuclear facilities, though American military officials believe that the Israelis would almost certainly require American equipment and support to do a thorough job. — David E. Sanger, New York Times, 8 Mar. 2025 From a legal perspective, law firms conduct thorough investigations and represent victims in their quest for compensation. — Arnold Sotelo, Forbes, 7 Mar. 2025 Daugherty said staff members at the shelters do a thorough behavioral assessment on every animal before it is decided whether to euthanize them. — Shambhavi Rimal, Fort Worth Star-Telegram, 6 Mar. 2025 Google says these more thorough responses, powered by its newer Gemini 2.0 model, should be better equipped to answer more complex, multifaceted questions as well as queries related to coding and advanced math. — Mack Degeurin, Popular Science, 6 Mar. 2025 See All Example Sentences for thorough

Word History

Etymology

Preposition, Adjective, and Adverb

Middle English thorow, from Old English thurh, thuruh, preposition & adverb

First Known Use

Adjective

15th century, in the meaning defined at sense 1

Preposition

before the 12th century, in the meaning defined above

Adverb

before the 12th century, in the meaning defined above

Time Traveler
The first known use of thorough was before the 12th century

Phrases Containing thorough

Rhymes for thorough

See All Rhymes for thorough

Browse Nearby Words

thorough
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Cite this Entry

“Thorough.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thorough. Accessed 11 Mar. 2025.

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Kids Definition

thorough

adjective
thor·​ough
ˈthər-ō,
ˈthə-rō
1
: marked by or carried out to completion : exhaustive
a thorough search
2
: careful about detail
a thorough worker
thoroughly adverb
thoroughness noun
Etymology

Adjective

Middle English thorow "thorough," from Old English thuruh, thurh "through" — related to thrill, through see Word History at thrill

More from Merriam-Webster on thorough

Nglish: Translation of thorough for Spanish Speakers

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