sickness

noun

sick·​ness ˈsik-nəs 

1

a

: ill health : illness

b

: a disordered, weakened, or unsound condition

2

: a specific disease

3

: nausea, queasiness

Synonyms

• illness
• indisposition
• unhealthiness
• unsoundness

Examples of sickness in a Sentence

He died from an unknown sickness.

she was plagued by sickness most of her adult life

Recent Examples on the Web

That sickness is caused by a virus typically spread by rats and mice. —Brian Niemietz, New York Daily News, 16 Apr. 2025

And how people can like this guy is— that's a sickness, actually. —Arick Wierson, MSNBC Newsweek, 15 Apr. 2025

Any cat can develop a sickness or dental problems, but having a baseline can alleviate anxieties and empower you to work with your vet to make the best life choices for your cat. —Molly Higgins, Wired News, 11 Apr. 2025

This year is already seeing an increase, not just in the number of animals sickened by the bloom but also in the intensity of their sickness when they’re found stranded on beaches. —Cnn.com Wire Service, Mercury News, 7 Apr. 2025

Word History

First Known Use

before the 12th century, in the meaning defined at sense 1a

Phrases Containing sickness

• acute mountain sickness
• African sleeping sickness
• altitude sickness
• decompression sickness
• milk sickness
• morning sickness
• motion sickness
• mountain sickness
• radiation sickness
• serum sickness
• sickness benefit
• sleeping sickness
• travel sickness

Rhymes for sickness

• quickness
• thickness
• homesickness
• seasickness

Kids Definition

sickness

noun

sick·​ness ˈsik-nəs 

1

: ill health : illness

2

: a specific disease : malady

3

: nausea sense 1

Medical Definition

sickness

noun

sick·​ness ˈsik-nəs 

1

: the condition of being ill : ill health

2

: a specific disease

3

: nausea