Genocide is the deliberate and systematic destruction, in whole or in part, of an ethnic, racial, religious, or national 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.
There are several conceptual difficulties in this interesting and ethically and politically important concept. Thus philosophers (political, language, social, and ethical philosophers) should be interested in this topic but there doesn't seem to be much.
Take forcible sterilizations of a group or the forced transferring and adoptions of a group to another. What happens if these sterilizations are not at all effective? Then is this an incidence of "attempted genocide"?
What about political "genocide"? Was the systematic extermination of the Kulaks during Stalin reign or the mass persecution of "counter revolutionaries" during the Cultural Revolution genocide?
What about the deliberate and systematic "destruction" of a group through cultural assimilation? The group's identity is lost but the group continues to exist qua some other identity.
I think racism is a fundamental aspect of what makes genocide evil and thus political/cultural "genocide," unless the political/cultural affiliation of a victimized group is also inextricably conflated with an ethno-racial identity in the eyes of the perpetrators and that this group is targeted because of their affiliation with that group qua ethno-racial group, it is not real genocide. The hallmark genocide of the 20th century is the Holocaust. It is a prototype for genocide. Jews were killed not because of their religion but because of their ethno-racial classification in the eyes of the Nazis. You can change your religion but your ethno-racial classification is due to your "essence" and is passed down through "blood" from generation to generation. So the intent (mens rea) has to be of a racist nature as depicted within the viewpoint of the perpetrators of genocide. Race and racialist thinking has to be part of the intent in a true genocide.
Additionally, genocide must be "systematic". But what does this mean? What if a non political body such as the entertainment industry suddenly decided to conspire against a minority group and portray individuals within that group as evil which then influences individuals in society to form mobs and lynch members of that minority group on a massive scale? Is that systematic enough? Does the "deliberate and systematic" nature of committing genocide have to be originating within a governmental body? What about racist grassroots organizations composed of nothing but ordinary citizens that happen to gain power and influence? What about a society that's a participatory democracy that has a referendum about whether or not to genocide one of its minority groups and then decides to do so?
There's lots of gray and ambiguity here.