heartburn

noun

heart·​burn ˈhärt-ˌbərn 

plural heartburns

: a burning discomfort behind the lower part of the sternum due especially to the backward flow of the acidic contents of the stomach into the esophagus

In any given month, about one-quarter of Americans suffer from heartburn, which is caused by reflux, or backward flow, of stomach acid into the esophagus.

—Clyde M. Burnham

Heartburn—painful reflux of stomach acid—can occur in a person with a perfectly intact esophagus.

—Paul G. Donohue

see acid reflux

Examples of heartburn in a Sentence

I like spicy food, but it gives me heartburn.

Recent Examples on the Web

Key Takeaways Wait two to three hours after eating before lying down to help prevent heartburn symptoms. —Karen Berger, Verywell Health, 1 May 2026

The most common side effects of fish oil supplements are gastrointestinal, including belching, nausea, heartburn and loose stools. —Bestreviews, Chicago Tribune, 27 Apr. 2026

One batch of a common heartburn drug was recalled over discolored tablets, according to the FDA. —Amber Brenza, Health, 24 Apr. 2026

But esophageal cancer can also cause throat pain and heartburn. —Cara Lynn Shultz, PEOPLE, 18 Apr. 2026

Word History

First Known Use

15th century, in the meaning defined above

Rhymes for heartburn

• adjourn
• concern
• decern
• discern
• downturn
• extern
• interne
• nocturne
• return
• sunburn
• unworn
• upturn

Kids Definition

heartburn

noun

heart·​burn -ˌbərn 

: a burning discomfort seeming to occur in the area of the heart and usually due to spasms which pass acid from the stomach into the esophagus

Medical Definition

heartburn

noun

heart·​burn -ˌbərn 

: a burning discomfort behind the lower part of the sternum due especially to the backward flow of the acidic contents of the stomach into the esophagus

called also cardialgia, pyrosis

see acid reflux compare water brash