breakthrough

American  

[breyk-throo] / ˈbreɪkˌθru /

noun

1. a military movement or advance all the way through and beyond an enemy's frontline defense.

2. an act or instance of removing or surpassing an obstruction or restriction; the overcoming of a stalemate.

   The president reported a breakthrough in the treaty negotiations.

3. any significant or sudden advance, development, achievement, or increase, as in scientific knowledge or diplomacy, that removes a barrier to progress.

   The jet engine was a major breakthrough in air transport.

4. Medicine/Medical. an infection, disease, disorder, or condition that occurs in an individual despite their having received a vaccine, medication, or treatment.

   Covid breakthroughs are usually less severe than infections in unvaccinated people, indicating that the vaccine is still doing its job of combating the virus.

---

adjective

1. constituting a breakthrough: Critics called it a breakthrough film.

   Their products are engineered with breakthrough technology.

   Critics called it a breakthrough film.

2. Medicine/Medical. relating to or being an infection, disease, disorder, or condition that occurs as a breakthrough: She experienced disabling breakthrough pain despite the high dose of painkillers she was taking.

   In the original vaccine trial, 89% of breakthrough infections were with a particular family of virus strains.

   She experienced disabling breakthrough pain despite the high dose of painkillers she was taking.

Etymology

Origin of breakthrough

First recorded in 1915–20; noun use of verb phrase break through

Explanation

An amazing discovery or a huge amount of progress can be called a breakthrough. The discovery of penicillin in 1928 was a breakthrough for modern medicine. A personal breakthrough might be overcoming your fear of spiders once and for all. A bigger breakthrough, one that affects many people, is the invention of indoor plumbing. There's a sense of suddenness and drama associated with most breakthroughs. The word started out with a military meaning of literally "breaking through a barrier" in 1918. By the 1930s, it came to have the second meaning of "abrupt solution."

Example Sentences

He recently asked OpenAI to lead a funding round for Helion after the nuclear-fusion startup fell behind on promises of a breakthrough energy source and began to run short on cash.

From The Wall Street Journal • Apr. 17, 2026

But authorities were unable to identify a suspect until the recent breakthrough.

From Los Angeles Times • Apr. 15, 2026

For patients waiting for the next breakthrough treatment, the answer matters.

From MarketWatch • Apr. 15, 2026

Then, amid what appeared to be increasing frustration after talks with Iran produced no breakthrough, came Sunday's attacks on Pope Leo.

From Barron's • Apr. 14, 2026

Enter, at last, Guido of Arezzo and his remarkable breakthrough.

From "The Story of Music" by Howard Goodall

Related Words

• boost
• development
• discovery
• finding
• gain
• hike
• improvement
• leap
• progress