adjective, un·health·i·er, un·health·i·est.

not in a state of good or normal health; in an unsound, weak, or morbid condition.
symptomatic of or resulting from bad health: an unhealthy pallor.
not conducive to good health; unhealthful: Night air was formerly considered unhealthy.
morally bad, harmful, or contaminating: unhealthy examples for the young.
dangerous; risky: Asking questions in this neighborhood can be unhealthy.

Origin of unhealthy

First recorded in 1585–95; un-1 + healthy
Related formsun·health·i·ly, adverbun·health·i·ness, noun

Synonyms for unhealthy

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for unhealthy

Contemporary Examples of unhealthy

Historical Examples of unhealthy

  • And I said that it seemed an unhealthy thing to dump all our refuse so close to the city.

    The Harbor

    Ernest Poole

  • Lorilleux, annoyed at not having any fat himself, said that it was soft and unhealthy.


    Emile Zola

  • And your English lakes—Vindermere, Grasmere they, then, unhealthy?

    Howards End

    E. M. Forster

  • To her mind there was something feverish and unhealthy in its vivid beauty.

    Audrey Craven

    May Sinclair

  • He also saw the unhealthy lines in his cheeks and round his mouth.

    The Golden Woman

    Ridgwell Cullum

British Dictionary definitions for unhealthy


adjective -healthier or -healthiest

characterized by ill-health; sick; unwell
characteristic of, conducive to, or resulting from ill-healthan unhealthy complexion; an unhealthy atmosphere
morbid or unwholesome
informal dangerous; risky
Derived Formsunhealthily, adverbunhealthiness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for unhealthy

1590s, "injurious to health," from un- (1) "not" + healthy. Earlier unhealthsome (1540s), unhealthful (1570s). Of persons, "sickly," it is attested from 1610s. Related: Unhealthily.

Online Etymology Dictionary, © 2010 Douglas Harper