exogenous

American  

[ek-soj-uh-nuhs] / ɛkˈsɒdʒ ə nəs /

adjective

1. originating from outside; derived externally.

2. Botany.

   1. (of plants, as the dicotyledons) having stems that grow by the addition of an annual layer of wood to the outside beneath the bark.

   2. pertaining to plants having such stems.

   3. belonging to the exogens.

3. Pathology. (of a disease) externally caused rather than resulting from conditions within the organism.

4. Biochemistry. of or noting the metabolic assimilation of proteins or other metabolites, the elimination of nitrogenous catabolites being in direct proportion to the amount of metabolites taken in.

5. Geology. exogenetic.

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exogenous British  

/ ɛkˈsɒdʒɪnəs /

adjective

1. having an external origin

2. biology

   1. developing or originating outside an organism or part of an organism

   2. of or relating to external factors, such as light, that influence an organism

3. psychiatry (of a mental illness) caused by external factors

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exogenous Scientific  

/ ĕk-sŏj′ə-nəs /

1. Originating or produced from outside an organism, tissue, or cell.

2. Compare endogenous

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Other Word Forms

• exogenism noun
• exogenously adverb

Etymology

Origin of exogenous

First recorded in 1820–30; exo- + -gen + -ous

Explanation

Something that's exogenous comes from somewhere else, from outside. If your village practices exogenous marriage, you'll need to find a mate from another village, one outside your own. Exogenous is the opposite of endogenous. If your village traditions favor endogenous marriage, you’ll marry somebody from your own village. In biology and medicine, especially psychiatry, the word exogenous is used to describe outside factors, something that originates from outside the organism. When you're identifying causes of disease, toxins in your environment would be exogenous causes (they come from outside you), while genetic predisposition (something inside you) would be considered an endogenous cause.

Example Sentences

"In a world of more shocks, of exogenous forces, they have no control over, what they have control over is getting the economy in good shape," she told AFP.

From Barron's • Apr. 9, 2026

He said while the company absorbed an exogenous shock linked to tariffs, which “disproportionately affecting ad spend from our top retail advertisers, this quarter also underscored where we need to move faster.”

From MarketWatch • Feb. 13, 2026

In Solow’s model, the big driver of growth was technological change, but it was exogenous.

From The Wall Street Journal • Oct. 13, 2025

"On our own analysis, the 'extra' cases serve to underline rather than undermine this aspect of the phenomena that are said to be distinctive in those cases of administration of exogenous insulin," they concluded.

From BBC • Jun. 26, 2025

Pith, the cellular centre of an exogenous stem, 138.

From The Elements of Botany For Beginners and For Schools by Gray, Asa

Related Words

• external