After reading what Varadkar said about genocide yesterday ("Varadkar rules out joining South African genocide case"), there are many things you could say. I'm going to gloss over whether a man who contradicts himself in mid argument is fit to be in government, and focus on a bigger issue.
Genocide is where somebody selectively kills part of a population of a certain race, religion, ethnicity, creed, etc.
It is not necessary to kill every member of of the target group, to commit a genocide.
Genocide is a two part process. The target population is first isolated in a certain place, then massacred. If non-target people are first given the opportunity to leave, before the massacre starts, then that is further evidence of genocide.
Common definitions of genocide (and there are several) focus on intent. Intent is difficult to prove. Definitions of crimes only make sense when they focus on the actual act, not on speculation about actor's intent.
A bombing is not a genocide, nor is a massacre. Isolating a certain population inside a walled off region, and then bombing it, is a genocide. Isolating a people in a certain region, then withdrawing the supply of water, or blocking the importation of medicine, is also genocide. Driving into a town and shooting everyone, is not genocide.