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.

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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

The key breakthrough came from understanding what disrupts dolomite as it forms.

From Science Daily • Apr. 20, 2026

While the network was careful to note that he had not been named a suspect, its minute-by-minute coverage suggested that this could be a major breakthrough.

From Slate • Apr. 19, 2026

The big breakthrough for Clannad came with the release of the theme tune from the TV series Harry's Game in 1982, which was set in Northern Ireland during the Troubles.

From BBC • Apr. 17, 2026

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

“I have fresh fish for sale ” Storing live fish to eat later had been a major breakthrough, he thought.

From "Hatchet" by Gary Paulsen

Related Words

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