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

Although people sometimes use animals informally to mean only vertebrates (animals with backbones) or even just mammals, in biology the term includes insects as well. — Encyclopedia Britannica, 14 Aug. 2026

Yet the underlying biology of aging remains a matter of uncertainty and debate. — Ingrid Wickelgren, Quanta Magazine, 14 Aug. 2026

Students studied English, science, mathematics, biology and literature alongside religious subjects. — Fatima Faizi, NPR, 14 Aug. 2026

Players can take control of enemies and use their abilities to explore, fight, and solve puzzles, while the creature’s biology changes the world in response to their actions. — Matt Gardner, Forbes.com, 12 Aug. 2026

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

• ology
• aetiology
• anthropology
• archaeology
• archeology
• audiology
• cardiology
• climatology
• cohomology
• cosmetology
• criminology
• demonology

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