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
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.
Noun
The breakthrough, described in a New England Journal of Medicine paper and presented at a conference in mid-December, is called blinatumomab, an immunotherapy drug delivered to patients over a 28-day IV drip. Seth Klamann, The Denver Post, 21 Dec. 2024 Prime Target follows Woodall’s Edward Brooks, a math genius (hence the reference to prime numbers) on the brink of a major breakthrough who senses someone may be trying to thwart his discovery. Lucy Ford, TIME, 20 Dec. 2024
Verb
But those efforts often struggled to break through the noise. Justin Worland, TIME, 20 Dec. 2024 This Christmas, allow that message to break through all the clutter. Chris Roemer, Baltimore Sun, 19 Dec. 2024 See all Example Sentences for breakthrough 

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 through

breakthrough

break time

Cite this Entry

“Breakthrough.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/breakthrough. Accessed 26 Dec. 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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