breakthrough

1 of 2

noun

break·​through ˈbrāk-ˌthrü 

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

Synonyms

Noun

• advance
• advancement
• enhancement
• improvement
• refinement

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

The only breakthrough came on Helfrick's home run, a 387-blast to left field for the freshman's third of the season. —Tom Murphy, arkansasonline.com, 27 Apr. 2024

The breakthrough came months after strikes at the Big Three Detroit automakers — Ford, General Motors and Jeep maker Stellantis, all of which have long been unionized. —J.j. McCorvey, NBC News, 24 Apr. 2024

Word History

First Known Use

Noun

1915, in the meaning defined at sense 3

Verb

1946, in the meaning defined above

Phrases Containing breakthrough

• breakthrough cases
• breakthrough infection

Kids Definition

breakthrough

noun

break·​through ˈbrāk-ˌthrü 

: a sudden advance in knowledge or technique

a breakthrough in medical science

Medical Definition

breakthrough

noun

break·​through ˈbrāk-ˌthrü 

: infection occurring in someone who is fully vaccinated against an infectious agent

—often used before another noun

breakthrough infections