: a sudden advance especially in knowledge or technique
a medical breakthrough
: a person's first notable success—often used before another noun
a breakthrough novelthe actress's breakthrough performance
: an act or instance of moving through or beyond an obstacle
a breakthrough in the talks between the region's leaders
a breakthrough agreement
: 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
warfare: an offensive military assault that penetrates and carries beyond a defensive line
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
The breakthrough finally came on Monday, when the genealogist called Miller and confirmed that the test was a match.—Daniel Wu, Washington Post, 26 Jan. 2023 The breakthrough came down to lasers focused on a small capsule of fuel.—Sara Lang, The Christian Science Monitor, 17 Jan. 2023 The breakthrough joins a string of cold cases being reexamined and sometimes solved around the country in recent years, including the Golden State Killer, through the emerging field of genetic genealogy.—Maryclaire Dale, USA TODAY, 14 Jan. 2023 The breakthrough joins a string of cold cases being reexamined and sometimes solved around the country in recent years, including the Golden State Killer, through the emerging field of genetic genealogy.—CBS News, 14 Jan. 2023 Thus, beyond the air meet’s ticket sales, the leading-edge pioneers of aviation came here — watching, learning, dreaming up the next breakthrough in flying technology.—Patt Morrisoncolumnist, Los Angeles Times, 10 Jan. 2023 The breakthrough shows that our ancestors may have had more in common with us than previously understood.—Devika Rao, The Week, 9 Jan. 2023 The breakthrough came after three days and 11 ballots on which the Texas Republicans, Michael Cloud of Victoria, Chip Roy of Austin and Keith Self of Plano, refused to back their party’s leader.—Dallas News, 6 Jan. 2023 But there are as many reasons to celebrate the Jeffries breakthrough as there are reasons to consider the complex truth about what his personal success may produce.—Janell Ross, Time, 3 Jan. 2023 See More
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.