The change of name reflected the move to organise topological classes such as cycles-modulo-boundaries explicitly into abelian groups.
This point of view is often attributed to Emmy Noether,[1] and so the change of title may reflect her influence.
The transition is also attributed to the work of Heinz Hopf,[2] who was influenced by Noether, and to Leopold Vietoris and Walther Mayer, who independently defined homology.
[3] A fairly precise date can be supplied in the internal notes of the Bourbaki group.
[4] This corresponds also to the period where homological algebra and category theory were introduced for the study of topological spaces, and largely supplanted combinatorial methods.