Centromer: region(er) af et kromosom, hvortil tentrådene er påhæftet under celledeling, således at datterkromosomerne kan ordnes i forhold til dattercellernes poler.
Centromere (Kinetochore): region(s) of a chromosome with which spindle fibers are associated during cell division, allowing orderly movement of daughter chromosomes to the poles of the daughter cells.