exogenous

adjective

ex·​og·​e·​nous ek-ˈsä-jə-nəs 

1

: produced by growth from superficial tissue

exogenous roots produced by leaves

2

a

: caused by factors (such as food or a traumatic factor) or an agent (such as a disease-producing organism) from outside the organism or system

exogenous obesity

exogenous psychic depression

exogenous market fluctuations

b

: introduced from or produced outside the organism or system

specifically : not synthesized within the organism or system

exogenously adverb

Examples of exogenous in a Sentence

Recent Examples on the Web

Braves outfielder Jurickson Profar has received a 162-game suspension after testing positive for exogenous testosterone. —Gabriel Burns, AJC.com, 4 Mar. 2026

Profar tested positive for exogenous testosterone and its metabolites, the commissioner's office said, which means testosterone that was not produced by his body. —CBS News, 4 Mar. 2026

An 'exogenous shock' from tariffs. —Alexei Oreskovic, Fortune, 13 Feb. 2026

Berryhill added that humans constantly juggle two competing forms of attention—endogenous, or top-down focus, and exogenous, or bottom-up distraction. —Melissa Fleur Afshar, MSNBC Newsweek, 11 Sep. 2025

Word History

Etymology

French exogène exogenous, from exo- + -gène (from Greek -genēs born) — more at -gen

First Known Use

1830, in the meaning defined at sense 1

Medical Definition

exogenous

adjective

ex·​og·​e·​nous ek-ˈsäj-ə-nəs 

variants also exogenic

ˌek-sō-ˈjen-ik 

1

: growing from or on the outside

exogenous spores

2

: caused by factors (as food or a traumatic event) or an agent (as a disease-producing organism) from outside the organism or system

exogenous obesity

exogenous depression

3

: introduced from or produced outside the organism or system

specifically : not synthesized within the organism or system compare endogenous

exogenously adverb