keto

1 of 3

adjective

ke·​to ˈkē-(ˌ)tō 

1

: of or relating to a ketone

also : containing the characteristic chemical group of a ketone consisting of a carbonyl attached to two carbon atoms

keto acids

2

: ketogenic sense 2

Since keto dieting is restrictive it's a good idea to consult with your doctor before starting.

—Ted Kallmyer

keto

2 of 3

noun

: a ketogenic diet

Salad is great for keto, but the dressing might not be. When in doubt, skip it.

—John Nicholson

Keto is a diet trend that cuts out carbohydrates and sugars to stop the blood sugar from spiking and have the body enter a state of ketosis, a process in which body burns fat for energy because it does not have enough carbohydrates to burn.

—Dan Boudreaux

keto-

3 of 3

combining form

: ketone : ketone body

ketosis

Examples of keto in a Sentence

Recent Examples on the Web

Adjective

That includes the keto diet and also veganism and vegetarianism. —Dominique Mosbergen, Time, 16 Oct. 2025

The keto diet used comprised 75% fat, 8.6% protein, and just over 3% carbohydrates. —New Atlas, 9 Oct. 2025

Noun

Experiments with preclinical mouse models suggest that those affected by this type of breast cancer and who have obesity could benefit from lipid-lowering therapies and steering clear of high-fat weight loss regimens—like the keto diet. —Hannah Millington, MSNBC Newsweek, 16 Oct. 2025

That includes the keto diet and also veganism and vegetarianism. —Dominique Mosbergen, Time, 16 Oct. 2025

Word History

Etymology

Adjective

(sense 1) from construing of keto- as an adjective; (sense 2) by shortening

Noun

by shortening

Combining form

ket(one) + -o-

First Known Use

Adjective

1891, in the meaning defined at sense 1

Noun

1994, in the meaning defined above

Phrases Containing keto

• keto diet

Rhymes for keto

• kato
• thereto

Medical Definition

keto

adjective

ke·​to ˈkēt-(ˌ)ō 

: of or relating to a ketone

also : containing a ketone group