biology

noun

bi·​ol·​o·​gy bī-ˈä-lə-jē 

1

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

advances in the field of biology

a biology textbook

2

a

: the plant and animal life of a region or environment

the biology of the rainforest

b

: the life processes especially of an organism or group

the biology of cancer cells

broadly : ecology

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

Recent Examples on the Web

Using new transit spectra from the James Webb Space Telescope (JWST), the researchers argued that the data were consistent with dimethyl sulfide, and possibly dimethyl disulfide — gases that on Earth are strongly associated with marine biology. —Sharmila Kuthunur, Space.com, 26 Dec. 2025

Science labs take you on journeys through topics in chemistry, physics and biology, and visitors will be doing, not just observing. —Bill Bootz, Charlotte Observer, 23 Dec. 2025

This kind of differential gene expression is central to some of biology’s greatest wonders — for example, the fact that all cells in the human body have the same DNA, and yet brain cells differ dramatically from liver, skin and blood cells. —Ivan Amato, Quanta Magazine, 22 Dec. 2025

Modern diet culture frames holiday eating as failure, but biology, history, and psychology tell a different story—one where feasting is not a lapse in discipline, but a deeply human ritual tied to survival, memory, and connection. —Marisa McMillan, Outside, 20 Dec. 2025

Word History

Etymology

German Biologie, from bi- + -logie -logy

First Known Use

1799, in the meaning defined at sense 1

Phrases Containing biology

• cell biology
• developmental biology
• evolutionary biology
• evolutionary developmental biology
• molecular biology

Rhymes for biology

• anthology
• apology
• astrology
• christology
• chronology
• conchology
• cosmology
• cryptology
• cytology
• doxology
• ecology
• ethnology

Kids Definition

biology

noun

bi·​ol·​o·​gy bī-ˈäl-ə-jē 

1

: a branch of knowledge that deals with living organisms and life processes

2

a

: the plant and animal life of a region or environment

b

: the life processes of an organism or group

biologist

-jəst 

noun

Etymology

from German Biologie "biology," derived from Greek bi-, bio- "life" and -logia "study, science"

Medical Definition

biology

noun

bi·​ol·​o·​gy -jē 

plural biologies

1

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

2

a

: 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