Definition. Hylomorphism category-theory F-algebra F-coalgebra Fix an endofunctor ๐น:๐๏ธโ๐๏ธ, a coalgebra ๐พ:๐โ๐น๐ and an algebra ๐ผ:๐น๐ตโ๐ต. A hylomorphism (or coalgebra-to-algebra morphism) from ๐พ to ๐ผ is a morphism โ:๐โ๐ต satisfying โ=๐พโ๐นโโ๐ผ.