organism

organism — noun

1. a complete living thing, from a bacterium to a tree, that lives as one individua

1.nounB2
Definition

a complete living thing, from a bacterium to a tree, that lives as one individual unit

Example

A single-celled organism moved across the glass under the microscope.

collocation: single-celled organism

One harmful organism entered the cut through the dirty river water.

harmful organism in water

Common collocations
  • single-celled organism
  • harmful organism
  • soil organisms
  • living organism
Synonyms
  • living thing

    the plain everyday phrase, less scientific than organism

  • life form

    often used in science or when speaking more generally about kinds of life

  • creature

    more everyday and usually used for animals, not plants or bacteria

  • being

    a very broad formal word that is less exact in biology

Grammar Patterns

a single-celled organism

harmful organisms in water

an organism can survive

Usage Note

Usually countable. Common in science contexts with words like cell, soil, water, and disease. Distinguish from organ: an organism is the whole living thing, while an organ is only one part of a body.

Common Mistakes

The heart is an organism.
The heart is an organ.
An organism is a whole living thing, not one body part.

2. a whole whose sections work together and affect one another, especially in compa

2.nounC1
Definition

a whole whose sections work together and affect one another, especially in comparisons with a body that is alive

Example

The writer describes the city as an organism with streets like veins.

describe something as an organism

Inside the small company, each team worked like part of one organism.

part of one organism

Common collocations
  • social organism
  • part of one organism
  • city as an organism
  • act as an organism
Synonyms
  • system

    the broadest word, without the image of a living body

  • whole

    stresses that the parts are taken together as one complete thing

  • structure

    focuses more on arrangement than on life-like interaction

  • body

    can suggest one united group, but it is less analytical than organism

Grammar Patterns

describe something as an organism

part of one organism

act as an organism

Usage Note

Usually appears in patterns like describe X as an organism or see X as one organism. Mostly used in formal writing or analysis, not as the ordinary word for a company, school, or group.

Common Mistakes

The school organism raised money for new books.
The school organization raised money for new books.
Organism is used for a living thing or for a system compared to one, not as the normal word for a group.

Word family

  • microorganism
    nounB2

Synonym discussion

Sense: noun/1

Organism is the scientific or formal word for any living thing that exists as its own unit, from a bacterium to a whale. Living thing is the plain everyday phrase and is best when you do not need a scientific tone. Life form often appears in science writing or in discussions of possible life on other planets, so it can sound broader and more abstract. Creature is more everyday and usually suggests an animal, not a plant or bacterium. Being is very broad and often sounds formal, philosophical, or religious. Use organism for biological accuracy: A single-celled organism was moving in the water. Use living thing for simple explanation: Every living thing needs water.

organism ↗living thinglife formcreature ↗being ↗

Common collocations

Nouns

  • complex organism
  • one organism

Phrases

  • parts of an organism
  • function as an organism

Etymology

FrenchEnglish

Organism first appeared in English with the older sense of organization. Its modern meanings were shaped by French organisme, and the word later came to mean either a living thing or a whole system whose parts depend on one another.