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 of sickness

• illness

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

Mao’s resolution treated each of these as a sickness that could sometimes be cured through a regimen of criticism and self-criticism in front of peers. — Andrew Mertha, Foreign Affairs, 17 Sep. 2026

In Lee Cronin’s The Mummy, evil is a native sickness that contaminates an otherwise perfect, unsullied child of empire. — Literary Hub, 15 Sep. 2026

There’s a mysterious sickness going around, apparently caused by a toxic fog that invisibly burns the skin of whoever comes into contact with it. — Beatrice Loayza, Variety, 9 Sep. 2026

In the case of the cyclospora outbreak, Taylor Farms initiated a recall of iceberg lettuce after reports of sickness emerged from across the country. — Dian Zhang, USA Today, 28 Aug. 2026

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