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

Metabolism is a key to life in large part because in any organism the exchange of materials and energy is essential for life, says Apai. —Bruce Dorminey, Forbes.com, 21 Aug. 2025

These living payloads will spend a month circling Earth, to help scientists gauge the effects of spaceflight on organisms and their various systems. —Mike Wall, Space.com, 20 Aug. 2025

Water is the medium in which all chemical reactions in an organism take place, and those reactions are finely tuned to a narrow range of ratios between water and salt, another essential ingredient in life’s chemistry. —Dan Samorodnitsky, Quanta Magazine, 11 Aug. 2025

These materials provide a slow and steady supply of plant nutrients that improve soil structure, promote movement of air and water, and are a good home for plant roots and soil organisms. —Nanette Londeree, Mercury News, 4 Aug. 2025

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
• statism
• sufism
• thomism
• tourism
• tropism
• abolitionism
• aldosteronism
• americanism

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