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 eating habits

unhealthy levels of lead

c

: involving or causing feelings or thoughts that are not normal and healthy

an unhealthy relationship

has an unhealthy interest in natural disasters

unhealthily

ˌən-ˈhel-thə-lē 

adverb

unhealthiness

ˌən-ˈhel-thē-nəs 

noun

Synonyms of unhealthy

• 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

Successive Delhi governments have had air pollution plans dating back to 1996, but decades on, the air remains dangerously unhealthy, especially at this time of year when colder air traps smoke and fumes from fireworks, crop-burning and heavy city traffic. —Esha Mitra, CNN Money, 23 Nov. 2025

The poster said the unhealthy relationship took a toll on both of them. —Ashley Vega, PEOPLE, 22 Nov. 2025

What Happens Next The EPA advises residents in affected areas across Georgia—especially those with heart or lung disease, older adults, children, and outdoor workers—to take steps to avoid exposure to the unhealthy air quality. —Amanda Greenwood, MSNBC Newsweek, 18 Nov. 2025

There’s no doubt very talented people work on Call of Duty and are often allowed to put out a banger amidst all the corporate chaos and unhealthy deadlines, yet 2025’s Black Ops 7 feels like a downer and a sign of the franchise crumbling under its own weight once again. —Fran J. Ruiz, Rolling Stone, 18 Nov. 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