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

Nevertheless, for centuries, debate has persisted over the agency of organisms. — Literary Hub, 14 Aug. 2026

The shells and skeletons of the organisms were ground up by the ocean waves into a white sand and compacted over time, forming a distinctively smooth and homogenous stone. — Marissa Meador, IndyStar, 14 Aug. 2026

In this layer, known as the deep biosphere, organisms’ primary source of energy is not sunlight, but gases and compounds leached from the rock. — James Dinneen, New Yorker, 13 Aug. 2026

Other microbes recycle nutrients by decomposing dead plants and animals, fix atmospheric nitrogen into forms that plants can use, and form essential partnerships with roots, insects, and other organisms. — Encyclopedia Britannica, 11 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