Go to 'thermo-' entry Go to 'dino-' entry Go to 'chondro-' entry Go to 'aero-' entry Go to '-logy' entry Go to 'thaumato-' entry Go to 'nano-' entry Go to '-sophy' entry Go to 'bucco-' entry Go to '-ism' entry Go to '-lysis' entry Go to 'galacto-' entry Go to '-anthropy' entry Go to 'pneumo-' entry Go to '-ploitation' entry Go to '-lithic' entry Go to '-sepalous' entry Go to 'onco-' entry Go to '-parous' entry Go to 'dermato-' entry Go to 'multi-' entry Go to 'dodeca-' entry Go to '-zoon' entry Go to 'vermi-' entry Go to 'crystallo-' entry Go to 'biblio-' entry Go to 'eco-' entry Go to 'juxta-' entry Go to 'facio-' entry
Affixes: the building blocks of English
Affixes: the building blocks of English

end(o)-

Internal; within.

[Greek endon, within.]

An endoscope is an instrument which can be introduced into the body to give a view of its internal parts; an endoskeleton is an internal skeleton, such as that of vertebrates; the endocardium (Greek kardia, heart) is the thin, smooth membrane which lines the inside of the chambers of the heart; the endometrium (Greek mētra, womb) is the mucous membrane lining the womb; endarterectomy (Greek ektomē, excision) is surgical removal of part of the inner lining of an artery.

The adjective endogenous refers to something having an internal cause or origin; endothermic to a reaction or process in chemistry accompanied by or requiring the absorption of heat; endocrine (Greek krinein, sift) refers to glands which secrete hormones or other products directly into the blood; endemic, restricted to a certain country or area, was formed in Greek (endēmios, native, based on dēmos, people).

Endo- is closely related to ento-; its opposite is ecto- or exo-.

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