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

Cities are ever-changing organisms, shedding elements of the past while retaining others. — Nina Metz, Chicago Tribune, 25 Sep. 2026

Photosynthetic organisms use arrays of pigments and proteins called light-harvesting complexes to soak up light. — Elise Cutts, Quanta Magazine, 23 Sep. 2026

The gut microbiome contains many types of bacteria, fungi, viruses, and other organisms. — Amber J. Tresca, Verywell Health, 23 Sep. 2026

This organism can reproduce at 145°F and can continue moving up to 147°F, setting a record for complex organisms. — Brittney Melton, NPR, 23 Sep. 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