It seems "endomorphism" is used both ways (in, presumably, different contexts). https://ncatlab.org/nlab/show/endomorphism https://ncatlab.org/nlab/show/endomo

It seems "endomorphism" is used both ways (in, presumably, different contexts). https://ncatlab.org/nlab/show/endomorphism https://ncatlab.org/nlab/show/endomorphism I think "endomorphism is a homomorphism ..." is more common, but notably is not the usage in Haskell (https://hackage.haskell.org/package/base/docs/Data-Monoid.html#t:Endo https://hackage.haskell.org/package/base/docs/Data-Monoid.ht...)