“Genocide is not merely a word for mass killing in general. In international law, per the 1948 Genocide Convention, it refers to any of the following five acts if they are “committed with intent to destroy, in whole or in part, a national, ethnical, racial or religious group”:
(a) Killing members of the group;
(b) Causing serious bodily or mental harm to members of the group;
(c) Deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in whole or in part;
(d) Imposing measures intended to prevent births within the group;
(e) Forcibly transferring children of the group to another group.
Under this definition, not every act of violence against civilians qualifies as an act of genocide — nor does every such act motivated by racial, national, or religious hatred. Instead, it is an act of genocide when it is part of a plan to “destroy” the target group — that is, to annihilate not just individual members but the group as a collective.
In the Russian case, establishing that Russian soldiers intentionally killed Ukrainian civilians is not enough to prove genocide. It wouldn’t even be enough if the soldiers said they did it because they hated Ukrainians. Instead, you would need to show that the killings were part of an intentional effort to wipe out the Ukrainian people.”
https://www.vox.com/23020696/ukraine-russia-genocide-allegations