mouthful

American  

[mouth-fool] / ˈmaʊθˌfʊl /

noun

plural

mouthfuls

1. the amount a mouth can hold.

2. the amount taken into the mouth at one time.

3. a small quantity.

4. Informal. a spoken remark of great truth, relevance, effectiveness, etc..

   You said a mouthful!

5. a long word or group of words, especially one that is hard to pronounce.

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mouthful British  

/ ˈmaʊθˌfʊl /

noun

1. as much as is held in the mouth at one time

2. a small quantity, as of food

3. a long word or phrase that is difficult to say

4. informal an abusive response

5. informal an impressive remark (esp in the phrase say a mouthful )

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mouthful Idioms  

1. see say a mouthful.

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Spelling

See -ful.

Etymology

Origin of mouthful

1375–1425; late Middle English. See mouth, -ful

Explanation

A mouthful is an amount of some substance that can fit in a person's mouth. If you eat a mouthful of chocolate cream pie, you consume a bite of it. A mischievous kid might spit a mouthful of water at her sister, while a thirsty athlete might gulp a mouthful of water after her workout. In both cases, the mouthful is as much water as can fit in their mouths. If you're not very hungry for dinner, you might just have a few mouthfuls of mashed potatoes — just a few bites, in other words. Another kind of mouthful is a long, complicated word, phrase, or sentence.

Example Sentences

If that seems like a mouthful, here’s the takeaway from researchers themselves: Allen Scheie, a physicist at Los Alamos National Laboratory, says the result “raises the bar for what can be expected from quantum computers.”

From Barron's • Mar. 26, 2026

It took only a few words mumbled with a mouthful of burger for Tom Curtis to strike a blow against his biggest competitor.

From The Wall Street Journal • Mar. 4, 2026

Rather than focusing on preventing long-term diseases, the goal becomes maintaining muscle mass, preventing weight loss and ensuring every mouthful delivers plenty of nutrients.

From Science Daily • Feb. 26, 2026

It also evenly distributes the fat, making every mouthful taste and feel the same.

From Slate • Jan. 28, 2026

“Which one gave him that last mouthful of gibberish?” asked Kojo.

From "The Smartest Kid in the Universe" by Chris Grabenstein