bi·ol·o·gy | \ bī-ˈä-lə-jē \

Definition of biology 

1 : a branch of knowledge that deals with living organisms and vital processes advances in the field of biology a biology textbook

2a : the plant and animal life of a region or environment the biology of the rain forest

b : the life processes especially of an organism or group the biology of cancer cells broadly : ecology

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Other words from biology

biologist \bī-ˈä-lə-jist \ noun

Examples of biology in a Sentence

advances in the field of biology the biology of the rain forest the biology of tumor cells
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Recent Examples on the Web

For years scientists have tried to unravel the biology behind this mysterious phenomenon. Esther Landhuis, Scientific American, "Could Brain Stimulation Slow Cancer?," 13 July 2018 The idea is that doctors can use genetic tests to tailor medical treatments to the specific biology of patients. Julia Belluz, Vox, "Many breast cancer patients don’t need chemo, a precision medicine study just found," 5 June 2018 Doing the same to biology could transform our approach to solving aging. WSJ, "Is There a Limit to the Human Lifespan?," 24 June 2018 In recent decades, scientists have come to recognize that nearly everything—from physics to biology to human behavior—is complex and indeterminate. Joseph Franklin, Scientific American, "Suicide Prediction Remains Difficult Despite Decades of Research," 11 June 2018 Ninth grade biology students helped to plant trees for the arboretum's new climate change garden which will open later this spring. Joan Rusek,, "Local kids eat healthy and teach adults about climate change: Valley Views," 13 May 2018 As an undergrad at Harvard, McCargar had started out majoring in physics and astronomy, but while hitchhiking across the country one summer he’d got caught up in the environmental movement and switched to biology. Naomi Fry, The New Yorker, "Scott Pruitt’s Dirty Politics," 3 Apr. 2017 From botany to biology to chemistry and on, each chapter explains the many sciences in making alcohol. Sarah Mupo, STAT, "The 39 best health and science books to read this summer," 25 June 2018 That feels like an engineering task to be undertaken once the cellular biology gets worked out. Joi Ito, WIRED, "Fake Meat, Served Six Ways," 2 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'biology.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of biology

1799, in the meaning defined at sense 1

History and Etymology for biology

German Biologie, from bi- + -logie -logy

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Phrases Related to biology

marine biologist

Statistics for biology

Last Updated

13 Sep 2018

Look-up Popularity

Time Traveler for biology

The first known use of biology was in 1799

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More Definitions for biology



English Language Learners Definition of biology

: a science that deals with things that are alive (such as plants and animals)

: the plant and animal life of a particular place

: the processes that occur in a living thing


bi·ol·o·gy | \ bī-ˈä-lə-jē \

Kids Definition of biology

: a science that deals with living things and their relationships, distribution, and behavior


bi·ol·o·gy | \ -jē \
plural biologies

Medical Definition of biology 

1 : a branch of science that deals with living organisms and vital processes

2a : the plant and animal life of a region or environment

b : the laws and phenomena relating to an organism or group

3 : a treatise on biology

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Comments on biology

What made you want to look up biology? Please tell us where you read or heard it (including the quote, if possible).


to deposit or conceal in a hiding place

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