unhealthy

adjective

un·​healthy ˌən-ˈhel-thē 

unhealthier; unhealthiest

1

: not conducive to health : not healthful

an unhealthy climate

unhealthy habits

unhealthy foods

2

: not in good health : sickly, diseased

unhealthy animals

3

a

: risky, unsound

an unhealthy economy

b

: of a harmful nature : bad, injurious

unhealthy levels of lead

c

: morally contaminated : corrupt, unwholesome

an unhealthy imagination

unhealthily

ˌən-ˈhel-thə-lē 

adverb

unhealthiness

ˌən-ˈhel-thē-nəs 

noun

Synonyms

• insalubrious
• noisome
• noxious
• sickly
• unhealthful
• unwholesome

Examples of unhealthy in a Sentence

Her skin looks blotchy and unhealthy.

Tests revealed an unhealthy level of lead in the water.

Eating honey can be unhealthy for babies.

He was stuck in an unhealthy relationship.

She has an unhealthy interest in natural disasters.

Recent Examples on the Web

More than half of American adults struggle with chronic health conditions — like type 2 diabetes, obesity and cardiovascular disease — for which unhealthy diets are a risk factor, according to the introduction to the new Scientific Report from the 2025 Dietary Guidelines Advisory Committee (DGAC). —Ivana Saric, Axios, 11 Dec. 2024

And that again is an unhealthy and unsustainable way to view myself. —Cara Lynn Shultz, People.com, 10 Dec. 2024

Air quality index forecasts show conditions are unhealthy for sensitive groups on the Peninsula, Santa Clara Valley, northern Alameda County, West Contra Costa County and parts of the North Bay. —Sierra Lopez, The Mercury News, 8 Dec. 2024

Wondering if your social media habits are unhealthy? —Mark Travers, Forbes, 6 Dec. 2024

Word History

First Known Use

1595, in the meaning defined at sense 1

Kids Definition

unhealthy

adjective

un·​healthy ˌən-ˈhel-thē 

1

: not conducive to good health : not healthful

an unhealthy climate

2

: not in good health : sickly, diseased

3

a

: risky, unsound

an unhealthy economy

b

: injurious, bad

unhealthily

-thə-lē 

adverb

unhealthiness

-thē-nəs 

noun

Medical Definition

unhealthy

adjective

un·​healthy -ˈhel-thē 

unhealthier; unhealthiest

1

: not conducive to health

an unhealthy climate

2

: not in good health : sickly

unhealthiness noun