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

And among parents, the fear of illnesses like polio, measles and other sicknesses were always present. —Romy Ellenbogen, Miami Herald, 18 Dec. 2025

Symptoms include diarrhea, fever and stomach cramps, with this sickness lasting from four to seven days, according to the county’s news release. —Emma Hall, Sacbee.com, 18 Dec. 2025

The Jorge family hopes their efforts will keep sickness from crashing the holiday party. —Bri Buckley, CBS News, 15 Dec. 2025

But novels devoted to sickness, Woolf suggests, would be criticized as lacking all this. —Literary Hub, 9 Dec. 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