English Reference

Word

breakthrough

Phoneticsbreak·through

US/ˈbɹeɪkˌθɹu/

UK/bɹˈeɪkθɹuː/

Definitions

01major discovery

B2 · Science

n. a sudden and important discovery or success, especially in science or medicine.

n. a significant and often sudden advance or discovery that overcomes a major obstacle or impasse.

“Scientists have made a major breakthrough in the treatment of the disease.”

“The research team announced a significant breakthrough in battery technology, potentially doubling the range of electric vehicles within the next decade.”

Antonyms

02military/sports penetration

C1

n. the act of breaking through a line of defense, like in a war or a game.

n. the act of penetrating an opponent's defensive line or fortifications.

“The army achieved a breakthrough after weeks of fighting at the border.”

“The striker's sudden breakthrough in the final minutes of the match caught the defenders completely off guard.”

Formal

Antonyms

03highly successful

B2

adj. describing a success that makes someone famous or shows great progress.

adj. characterised by major progress or marking a significant transition to a higher level of success or recognition.

“The young actress had her breakthrough role in a popular TV drama.”

“Following several years of modest sales, the band finally achieved breakthrough success with their third studio album.”

04medical infection after vaccine

C1 · Medicine

adj. describing an illness that someone catches even though they were vaccinated against it.

adj. relating to the contraction of a disease by an individual who has been vaccinated or has existing immunity.

“The doctor explained that breakthrough infections are usually very mild.”

“Public health officials monitored the rate of breakthrough cases to determine if the vaccine's efficacy was waning over time.”

Technical

Usage

Usually modifies 'infection' or 'case'.

Real-World Examples

“Her breakthrough role came in 2001 when she was cast as Dawn, the sympathetic and witty receptionist in Gervais and Stephen Merchant's Bafta-winning office-based sitcom.”
BBC News · 14 Aug 2026
“The international team made the breakthrough after focusing their attention on a mysterious red spot in images of the early universe captured by Nasa’s James Webb space telescope.”
The Guardian · 12 Aug 2026
“It was a major breakthrough, said Mathulwe, because while there are chemical treatments for dealing with the caterpillars in the early stages of life, nothing has proven effective against mature populations.”
The Guardian · 12 Aug 2026
“The breakthrough could reduce structural material costs by roughly 40 times and make seawater-based hydrogen production far more economical.”
ScienceDaily · 11 Aug 2026

Etymology

From break + through. Compare German Durchbruch and Dutch doorbraak (“breakthrough”, literally “through-break”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Collocations

breakthroughs innovations

Domains

MedicineMilitarySports

This entry

Level
C1 · Advanced
Frequency
Frequent
Updated

Scan code

englishreference.com/q/breakthrough

English Reference