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

The show is about inequality, the trauma of puberty, and unhealthy family dynamics. — Jason P. Frank, Vulture, 5 Nov. 2026

But in the meantime, fighting for people’s health against industrial pollution of America’s air and water or pumping out unhealthy food has not been the defining rallying cry for the party in recent years. — Brinda Adhikari, STAT, 5 Nov. 2026

For the insurance companies, the risk pool has more unhealthy, older people than in previous years as younger and relatively healthier people leave the insurance market because of affordability. — Nicole Villalpando, Austin American Statesman, 5 Nov. 2026

The good news is that the study also found that movement — in the right amounts and at the right times — staves off muscle laziness and might make sitting a little less unhealthy. — Gretchen Reynolds, Washington Post, 28 Oct. 2026

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