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

While heartburn medication can be a lifesaver for those suffering from gastric reflux, several studies over the years have indicated that the drugs could increase stomach cancer risks more than threefold. —New Atlas, 22 Jan. 2026

Consuming more can cause heartburn, diarrhea, and abdominal discomfort. —Mark Gurarie, Health, 20 Jan. 2026

Nothing comes easy for these Broncos, but the road to the Super Bowl LX still runs through Denver after a heartburn-inducing 33-30 overtime win over the Bills on Saturday at Empower Field. —Joe Nguyen, Denver Post, 17 Jan. 2026

Henry details how the heartburn relief brand helps him with his diet and routine. —Dj Siddiqi, Forbes.com, 17 Jan. 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