noun, often attributive
break·​through | \ ˈbrāk-ˌthrü How to pronounce breakthrough (audio) \

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

broke through; broken through; breaking through; breaks 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

Antonyms: Noun

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Examples of breakthrough in a Sentence

Noun 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 With an effective range of 1,000 nautical miles—at 1,150 miles, that's about 1,130 miles farther than existing guns—the SLRC could be a truly revolutionary breakthrough in artillery warfare. Kyle Mizokami, Popular Mechanics, "The Army's Mind-Bending 1,000-Mile Cannon Is Coming. Could It Bring Back Battleships?," 16 Oct. 2020 Although monoclonal antibodies gained public visibility when used to heal the U.S. president, this is a breakthrough that belongs to the world — and perhaps to no one more than Dr. Jean-Jacques Muyembe-Tamfum. Deborah Jenson, STAT, "Thank this Ebola-fighting African doctor for monoclonal antibody treatments," 15 Oct. 2020 Beye's work, aided greatly by Crispr, was a huge breakthrough in bee biology, and his research continues to be incredibly controversial to beekeepers and even some scientists. Bernhard Warner, Fortune, "Markets climb as Wall Street grows more content with a possible Biden presidency," 8 Oct. 2020 If true, this would be a breakthrough of epic proportions. Paul Douglas, Star Tribune, "Shorts-Worthy Friday and a Fine Weekend as "Delta" Approaches Louisiana," 7 Oct. 2020 The treatment, Hoopes felt, had the potential to be a breakthrough that could save lives, both human and canine. Daniel Oberhaus, Wired, "A Common Plant Virus Is an Unlikely Ally in the War on Cancer," 5 Oct. 2020 In addition, there were high expectations that this - Garoppolo’s second full season as a starter under Shanahan - could be a breakthrough. Ann Killion,, "If Garoppolo is sidelined, injury’s full effect won’t be felt for weeks," 20 Sep. 2020 The next big catalyst for markets will be a breakthrough on a Covid-19 vaccine and the US election in November. Julia Horowitz, CNN, "The economic recovery hangs in the balance as winter approaches," 20 Sep. 2020 Lawmakers in Congress continue to negotiate a plan to renew the additional aid to unemployed Americans, but there is no breakthrough in sight. James Barragán, Dallas News, "Feds end Trump’s plan for additional $300 in unemployment benefits after less than a month," 9 Sep. 2020

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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Time Traveler for breakthrough

Time Traveler

The first known use of breakthrough was in 1915

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Statistics for breakthrough

Last Updated

20 Oct 2020

Cite this Entry

“Breakthrough.” Dictionary, Merriam-Webster, Accessed 29 Oct. 2020.

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More Definitions for breakthrough


How to pronounce break through (audio)

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 How to pronounce breakthrough (audio) \

Kids Definition of breakthrough

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

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Comments on breakthrough

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