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

• poisonous
• toxic
• unhealthful
• unwholesome
• sickly
• noxious

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

What to Know On Friday, the Air Quality Index (AQI) was expected to reach the purple category (between 201 and 300), or the very unhealthy level. —Anna Skinner, MSNBC Newsweek, 11 July 2025

Here’s what she’s learned about how to spot bad bosses and avoid unhealthy workplaces. —Sophie Caldwell, CNBC, 11 July 2025

People should consider remaining indoors and limiting outdoor activity when there’s heavy smoke, state officials said, and if visibility is less than five miles, smoke in the air has reached unhealthy levels. —John Aguilar, Denver Post, 10 July 2025

From season to season on Outer Banks, my appearance has changed with lots of factors: stress, breakups, healthy or unhealthy habits with food. —Brennan Kilbane, Allure, 10 July 2025

Word History

First Known Use

1595, in the meaning defined at sense 1

Rhymes for unhealthy

• healthy
• stealthy
• wealthy

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