combining form
or endo-
Etymology: French, from Greek, from endon within, at home, from en in + -don (perhaps akin to Latin domus house) — more at in , timber
1.
a. : within : inside
End amoeba
endo scope
b. : taking in : requiring
end ergonic
— opposed to exo-
2. endo-
a. : forming a bridge between two atoms in a cyclic system or having a bond or bivalent radical regarded as a bridge
endo ethylenic bridge
1,4- endo methylene-cyclohexane
b. sometimes italic : having one or more substituents directed inward — in names of stereoisomeric compounds containing a 6-membered ring in its boat form
2,5-methylene- endo -cyclohexyl-amine
— compare exo- b
3. : endocardium and
endo pericarditis