Define the terms xenophobia and genocide. What is the significance of each word in the context of this novel?

xenophobia -intense or irrational dislike or fear of people from other countries.

International definition of Genocide - "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..."

In Ender's Game Earth's population is xenophobic in that it is very insulated and scared of anyone different like the "buggers". They also try to wipe out the entire bugger population which is genocide.