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

And a diplomatic breakthrough with Tehran appears nowhere in sight.

From Los Angeles Times • May 2, 2026

It’s the kind of cultural and commercial breakthrough that we haven’t seen since the iPhone—and it happened largely without him.

From Slate • Apr. 30, 2026

The breakthrough relied on contributions from several research centers across Europe.

From Science Daily • Apr. 30, 2026

The forecast also anticipates no changes in U.S. tariffs on Canadian goods—so neither a breakthrough on U.S.-Canada trade talks nor an escalation in U.S. levies.

From The Wall Street Journal • Apr. 29, 2026

Your father thinks he is real close to a breakthrough on his sneaker project.

From "Holes" by Louis Sachar

Related Words

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