Violence or other hostile behavior arising when an ethnic group either feels itself under threat, or where it seeks to assert its superiority or dominance over other groups.

The internal individual struggle resulting from incompatible or opposing needs, drives, or external and internal demands. In group interactions, competitive or opposing action of incompatibles: antagonistic state or action (as of divergent ideas, interests, or persons). (from Merriam-Webster's Collegiate Dictionary, 10th ed)