ENGLISH
REFERENCE

organism

n. countable
B2 Upper Intermediate US //ˈɔɹɡəˌnɪzəm// UK //ˈɔːɡənˌɪzəm// or·gan·ism Archaic

n. any living thing, such as an animal, a plant, or a tiny bacteria. You use this word to talk about life in a scientific way.

n. an individual living system, such as an animal, plant, fungus, or bacterium, capable of response to stimuli, reproduction, growth, and homeostasis.


SIMPLE

The pond is full of tiny organisms that we cannot see.

CONTEXTUAL

Scientists are studying how this specific organism survives in the extreme heat of deep-sea vents.

COMPLEX

Every organism within the ecosystem plays a vital role in maintaining the delicate balance of nutrient cycles and energy flow through the food web.

Synonyms
Origin

First attested in 1701; from organ + -ism, from Ancient Greek ὄργανον (órganon, “a tool, instrument”), from Proto-Indo-European *werǵ- (“work”). Compare New Latin organismus.

Usage

Commonly used in biological and environmental contexts to refer to a single living entity.

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