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

According to the companies, the cetirizine hydrochloride tablets may have been cross-contaminated with ranitidine, which is used to treat heartburn, acid indigestion and sour stomach. — Saleen Martin, USA Today, 21 July 2026

This year’s primary for governor caused heartburn among both Democrats and Republicans who feared getting locked out of the November general election. — Ben Paviour, Sacbee.com, 16 July 2026

Some Probiotic Studies Show Acid Reflux Improvement Gastroesophageal reflux (also called acid reflux, or heartburn) occurs when the contents of your stomach flow up into the esophagus. — Verywell Health, 1 July 2026

That sensation, also known as heartburn, is due to acidic contents of your stomach flowing upward into your esophagus. — Sarah Klein, Time, 30 June 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