ecology

American  

[ih-kol-uh-jee, ee-kol-] / ɪˈkɒl ə dʒi, iˈkɒl- /

Archaic, oecology

noun

plural

ecologies

1. the branch of biology dealing with the relations and interactions between organisms and their environment, including other organisms.

2. the set of relationships existing between organisms and their environment.

   Inflowing rivers introduce nutrients and sediments that are important for the ecology of the lake.

3. the set of relationships existing between any complex system and its surroundings or environment.

   In the ecology of healthcare, both politics and technology play a key role.

4. Also called human ecology.  the branch of sociology concerned with the spacing and interdependence of people and institutions.

5. advocacy for the protection of natural resources from pollution or its effects; environmentalism.

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ecology British  

/ ɪˈkɒlədʒɪ /

noun

1. the study of the relationships between living organisms and their environment

2. the set of relationships of a particular organism with its environment

3. the study of the relationships between human groups and their physical environment

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ecology Scientific  

/ ĭ-kŏl′ə-jē /

1. The scientific study of the relationships between living things and their environments.

2. Also called bionomics

3. A system of such relationships within a particular environment.

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ecology Cultural  

1. The study of living things, their environment, and the relation between the two.

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Related Words

See ecosystem ( def. ).

Other Word Forms

• ecologic
  adjective
• ecological
  adjective
• ecologically
  adverb
• ecologist
  noun
• unecological
  adjective
• unecologically
  adverb

Etymology

Origin of ecology

First recorded in 1870–75; earlier oecology, from German Ökologie, from Greek oîk(os) “house, dwelling” + -o- + German -logie -logy; term introduced by E. H. Haeckel (1834–1919)

Explanation

The noun ecology describes the environment as it connects to living things, or the branch of biology that studies that environment. The German zoologist Ernst Haeckel coined the word ecology almost 150 years ago, and it should come as no surprise — his being a serious scientist and all — that he combined a couple of Greek words to do it. Oikos means "habitation" and -ology means "the study of." So ecology started off as the study of where things live. More and more, though, the word is used interchangeably with environment.

Example Sentences

Jon Gould, dean of UC Irvine’s School of Social Ecology, said the level of disapproval for Trump is striking given Orange County’s generally close political divide.

From Los Angeles Times • May 6, 2026

The behavior was reported this week in the journal Ecology and Evolution and was observed by entomologist Mark Moffett, a research associate at the Smithsonian's National Museum of Natural History.

From Science Daily • Apr. 14, 2026

The findings are published in the journal Molecular Ecology in a paper titled 'Social structure and interactions differentially shape aerotolerant and anaerobic gut microbiomes in a cooperative breeding species.'

From Science Daily • Apr. 13, 2026

“The idea of utilizing the urban forest for lumber started as a business idea in relation to the Urban Ecology Project, a business dedicated to utilizing urban resources.”

From Los Angeles Times • Apr. 8, 2026

I join the Ecology Club, and Sarah asks me to talk about endangered tigers at our next meeting.

From "You Bring the Distant Near" by Mitali Perkins

Related Words

• conservation
• preservation