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

Opioids, whether endogenous or those found in narcotics (called exogenous opioids), bind to opioid receptors located on the outer membrane of nerve cells in the brain, spinal cord, and other organs. —Dr. Sanjay Gupta, CNN Money, 26 Aug. 2025

Doing the right thing is the right way to inoculate your business against exogenous events, while positioning your brand for sustainable growth in even the most trying of times. —Michael Ringman, Forbes.com, 30 June 2025

Any exogenous shock such as a trade war or a real war may be both a contributing cause and proximate trigger for a crisis. —Edward Lotterman, Twin Cities, 15 June 2025

Major League Baseball announced Sunday that Philadelphia Phillies pitcher Jose Alvarado has been suspended 80 games after testing positive for exogenous Testosterone. —Jon Paul Hoornstra, MSNBC Newsweek, 18 May 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