breakthrough

1 of 2

noun

break·​through ˈbrāk-ˌthrü How to pronounce breakthrough (audio)
plural breakthroughs
1
a
: a sudden advance especially in knowledge or technique
a medical breakthrough
b
: a person's first notable success
often used before another noun
a breakthrough novel
the actress's breakthrough performance
2
a
: an act or instance of moving through or beyond an obstacle
a breakthrough in the talks between the region's leaders
a breakthrough agreement
b
: an instance of passing through a barrier or protection
The ice under the surface begins to deteriorate, increasing the risk of breakthroughs.Vicki Winger
specifically, medical : infection occurring in someone who is fully vaccinated against an infectious agent
A vaccine breakthrough occurs when a person tests positive for COVID-19 two weeks after being fully vaccinated against the disease … David Rasbach
often used before another noun
Two other CDC studies of breakthrough cases at nursing homes showed the vaccines protected residents, even when the virus spread through the homes. Maura Dolan
… the academy recently recommended that children receive two doses of the chicken pox vaccine, rather than just one, because the additional dose bolsters immunity and may help reduce breakthrough infection. Maria Raven
3
warfare : an offensive military assault that penetrates and carries beyond a defensive line

break through

2 of 2

verb

broke through; broken through; breaking through; breaks through

intransitive verb

: to make a breakthrough

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.
Recent Examples on the Web
Noun
And Belgium’s Flemish separatist movement have failed to make the breakthrough many feared. Max Hastings, Twin Cities, 12 June 2024 That breakthrough came after Skydance worked to sweeten the deal and give nonvoting shareholders the ability to exit the company at a slight premium. Meg James, Los Angeles Times, 11 June 2024
Verb
The Athletics broke through for the game’s first run in the sixth against Bassitt, with Max Schuemann scoring on a wild pitch. Jerry McDonald, The Mercury News, 7 June 2024 Known for his roles in genre television, Quinto first broke through with his performance as superpower-stealing serial killer Sylar in NBC's Heroes. Christian Holub, EW.com, 3 June 2024 See all Example Sentences for breakthrough 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'breakthrough.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

Noun

1915, in the meaning defined at sense 3

Verb

1946, in the meaning defined above

Time Traveler
The first known use of breakthrough was in 1915

Dictionary Entries Near breakthrough

break the truce

breakthrough

break through

Cite this Entry

“Breakthrough.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/breakthrough. Accessed 24 Jun. 2024.

Kids Definition

breakthrough

noun
break·​through ˈbrāk-ˌthrü How to pronounce breakthrough (audio)
: a sudden advance in knowledge or technique
a breakthrough in medical science

Medical Definition

breakthrough

noun
break·​through ˈbrāk-ˌthrü How to pronounce breakthrough (audio)
: infection occurring in someone who is fully vaccinated against an infectious agent
often used before another noun
breakthrough infections

More from Merriam-Webster on breakthrough

Last Updated: - Updated example sentences
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