physiology

American  

[fiz-ee-ol-uh-jee] / ˌfɪz iˈɒl ə dʒi /

noun

1. the branch of biology dealing with the functions and activities of living organisms and their parts, including all physical and chemical processes.

2. the organic processes or functions in an organism or in any of its parts.

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physiology British  

/ ˌfɪzɪˈɒlədʒɪ /

noun

1. the branch of science concerned with the functioning of organisms

2. the processes and functions of all or part of an organism

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physiology Scientific  

/ fĭz′ē-ŏl′ə-jē /

1. The scientific study of an organism's vital functions, including growth and development, the absorption and processing of nutrients, the synthesis and distribution of proteins and other organic molecules, and the functioning of different tissues, organs, and other anatomic structures. Physiology studies the normal mechanical, physical, and biochemical processes of animals and plants.

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physiology Cultural  

1. The study of the function of living things, including processes such as nutrition, movement, and reproduction. (Compare anatomy and morphology.)

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Other Word Forms

• physiologist noun

Etymology

Origin of physiology

First recorded in 1555–65; from Latin physiologia, from Greek physiología “science of natural causes and phenomena”; physio-, -logy

Compare meaning

How does physiology compare to similar and commonly confused words? Explore the most common comparisons:

• physiology vs. biology

Explanation

Physiology is the branch of biology that deals with the functions and processes of living organisms, both animals and plants. It's biology in motion. Physiology includes everything from how a single cell functions, to what makes your nerve receptors work, how your pancreas releases insulin, and what happens to your muscles when you exercise. Technology has made for great leaps in the science of physiology. The electron microscope, for instance, allows you to see down to even the molecules of the cell, and radioactive isotopes provide the means to track the movement of substances within an organism.

Example Sentences

“More people want to use them,” said Lauren Colenso-Semple, a muscle physiology researcher and science communication specialist who follows scientific studies of peptides as part of her work.

From Salon • Apr. 4, 2026

Current prescribing criteria center on body mass index thresholds and glycemic targets, metabolic markers that tell us something about a patient’s need for weight loss but nothing about their underlying GLP-1 physiology.

From Slate • Mar. 22, 2026

They depend on a delicate balance of climate, tree physiology, and farming techniques.

From BBC • Feb. 19, 2026

Contributors from the University of Toledo included Sailaja Paruchuri, professor of physiology and pharmacology, and Lakshminarayan Teegala, assistant professor of physiology and pharmacology.

From Science Daily • Jan. 27, 2026

Since completing my Ph.D. in 1961, I have divided my scientific research efforts between two fields: molecular physiology on the one hand, evolutionary biology and biogeography on the other hand.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond