organism

noun

or·​gan·​ism ˈȯr-gə-ˌni-zəm 

1

: a complex structure of interdependent and subordinate elements whose relations and properties are largely determined by their function in the whole

The nation is not merely the sum of individual citizens at any given time, but it is a living organism, a mystical body … of which the individual is an ephemeral part …

—Joseph Rossi

2

: an individual constituted to carry on the activities of life by means of parts or organs more or less separate in function but mutually dependent : a living being

a multicellular organism

organismic

ˌȯr-gə-ˈniz-mik 

adjective

or less commonly organismal

ˌȯr-gə-ˈniz-məl 

organismically

ˌȯr-gə-ˈniz-mi-k(ə-)lē 

adverb

Examples of organism in a Sentence

A human being is a complex organism.

Recent Examples on the Web

Temperature and moisture levels also affected organism activity, particularly if conditions were too cold or too dry, as did soil nutrient levels. — Jennifer Ouellette, ArsTechnica, 27 Aug. 2026

These spots also had the highest levels of organic matter needed for vital bacteria, fungi, earthworms, and other underground organisms. — Andrew Paul, Popular Science, 26 Aug. 2026

The Louisiana Department of Health announced last week a resident had likely contracted the organism, known as Naegleria fowleri, while swimming in Lake Claiborne which is about 30 miles northwest of Ruston. — Diego Mendoza, CNN Money, 24 Aug. 2026

The world’s next high-tech gold rush might start with a tiny organism clinging to a backyard rock. — Mrigakshi Dixit, Interesting Engineering, 24 Aug. 2026

Word History

First Known Use

circa 1774, in the meaning defined at sense 1

Phrases Containing organism

• genetically modified organism
• mycoplasma-like organism
• pleuropneumonia-like organism

Rhymes for organism

• autism
• fascism
• racism
• sikhism
• sophism
• statism
• sufism
• thomism
• tourism
• tropism
• abolitionism
• aldosteronism

Kids Definition

organism

noun

or·​gan·​ism ˈȯr-gə-ˌniz-əm 

1

: something having many related parts that function together as a whole

2

: an individual living thing that carries on the activities of life by means of organs which have separate functions but are dependent on each other : a living person, plant, or animal

organismic

ˌȯr-gə-ˈniz-mik 

adjective

Medical Definition

organism

noun

or·​gan·​ism ˈȯr-gə-ˌniz-əm 

: an individual constituted to carry on the activities of life by means of organs separate in function but mutually dependent : a living being

organismic

ˌȯr-gə-ˈniz-mik 

adjective

also organismal

-məl 

organismically

-mi-k(ə-)lē 

adverb