noun, often attributive
break·​through | \ˈbrāk-ˌthrü \

Definition of breakthrough 

(Entry 1 of 2)

1 warfare : an offensive military assault that penetrates and carries beyond a defensive line

2 : an act or instance of moving through or beyond an obstacle a breakthrough in the talks between the region's leaders a breakthrough agreement

3a : a sudden advance especially in knowledge or technique a medical breakthrough

b : a person's first notable success a breakthrough novel the actress's breakthrough performance

break through


Definition of break through (Entry 2 of 2)

intransitive verb

: to make a breakthrough

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Synonyms & Antonyms for breakthrough

Synonyms: Noun

advance, advancement, enhancement, improvement, refinement

Antonyms: Noun


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Examples of breakthrough in a Sentence


Researchers say they have made a major breakthrough in cancer treatment. The police have announced a breakthrough in the murder case. This job could be the breakthrough she's been waiting for.
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Recent Examples on the Web: Noun

On the final day of Denmark's Roskilde Festival on Saturday (July 7), the thousands-strong crowd lost their minds to the chorus of the smash, which served as Dua Lipa's international breakthrough in 2017. Hilary Hughes, Billboard, "Dua Lipa Celebrates One Year of Her 'Powerful' Smash Single 'New Rules'," 7 July 2018 It was hailed by activists as a breakthrough that advances individual rights and freedom of thought. Washington Post, "Court: S.Korea must allow alternative for military objectors," 29 June 2018 Friday night classified as a breakthrough of sorts for Brent Suter. Todd Rosiak, Milwaukee Journal Sentinel, "Brent Suter does it all for the Brewers in blowout victory," 16 June 2018 The devices are currently in use in at least five states and five federal agencies, seen as a breakthrough in collecting evidence from encrypted devices. Russell Brandom, The Verge, "Apple will update iOS to block police hacking tool," 13 June 2018 While hailed by the EU Commission as a major breakthrough, permanent joint military forces are a long way off. Gregory Viscusi,, "Trump Nears the Rubicon With Allies at NATO Summit in Four Weeks," 12 June 2018 President Trump on Tuesday touted his unprecedented meeting with North Korean leader Kim Jong Un as a breakthrough that would ease decades of tensions that have made the Korean Peninsula one of the most dangerous places on Earth. Susan Page, USA TODAY, "Analysis: When Trump met Kim, the handshake was more historic than the words," 12 June 2018 Therapy can be a tricky, even reductive thing to dramatize, but if the AA scenes run a bit long, Van Sant gives them a vivid open-endedness: Every answer and breakthrough brings with it another question. Justin Chang,, "Review: Joaquin Phoenix stars in the captivating addiction drama 'Don't Worry, He Won't Get Far on Foot'," 12 July 2018 Recent breakthroughs let phone makers embed the fingerprint reader inside the screen. Geoffrey Fowler,, "Future Phones: They Fold Like Napkins, Have 9 Cameras, Charge Over Thin Air," 6 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'breakthrough.' 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 breakthrough


1915, in the meaning defined at sense 1


1946, in the meaning defined above

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Last Updated

8 Nov 2018

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Time Traveler for breakthrough

The first known use of breakthrough was in 1915

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More Definitions for breakthrough



English Language Learners Definition of breakthrough

: a sudden increase in knowledge, understanding, etc. : an important discovery that happens after trying for a long time to understand or explain something

: a person's first important success


break·​through | \ˈbrāk-ˌthrü \

Kids Definition of breakthrough

: a sudden advance or successful development a breakthrough in medical research

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