As per "American Holocaust, Columbus and the Conquest of the New World, David Stannard, Oxford University Press, ISBN 0-19-507581-1 the term "genocide" was coined by Raphael Lemkin in his book, "Axis Rule in Occupied Europe, published in 1944. His thinking is summarized by Frank Chalk and Kurt Jonassohn. pp. 279-280:
Under Lemkin's definition, genocide was the coordinated and planned annihilation of a national, religious, or racial group by a variety of actions aimed at undermining the foundations essential to the survival of the group as a group. Lemkin conceived of genocide as 'a composite of different acts of persecution or destruction.' His definition included attack on political and social institutions, culture, language, national feelings, religion, and the economic existence of the group. Even nonlethal acts that undermined the liberty, dignity, and personal security of members of a group constituted genocide if they contributed to weakening the vitality of the group. Under Lemkin's definition, acts of ethnocide- a term coined by the French after the war to cover the destruction of a culture without the killing of its bearers-also qualified as genocide.
Lemkin stated that "Genocide has two phases: one, destruction of the national pattern of the oppressed group: the other, the imposition of the national pattern of the oppressor." This has most certainly been the case as regards the First Nations.
American Holocaust, pp. 279. United Nations General Assembly resolution, 1946:
Genocide is the denial of the right of existence to entire human groups, as homicide is the denial of the right to live of individual human beings; such denial of the right of existence shocks the conscience of mankind, results in great losses to humanity in the form of cultural and other contributions represented by these groups, and is contrary to moral law and to the spirit and aims of the United Nations. Many instances of such crimes of genocide is a matter of international concern. The General Assembly Therefore, Affirms that genocide is a crime under international law which the civilized world condemns, and for the commission of which principals and accomplices-whether private individuals, public officials or statesmen, and whether the crime is committed on religious, racial, political or any other grounds-are punishable.
pp. 280 - Genocide Convention of the United Nations (1948):
...Article II- In the present Convention, genocide means any of the following acts committed with intent to destroy, in whole or in part, a national, ethnical, racial, or religious group, as such: (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.