Ethnocentricity is a noun for the quality of being ethnocentric: the habit of putting your own race, nation, or group at the centre and treating other ways as lesser or odd. Writers use it with disapproval, mostly in academic or careful discussion, not in casual talk. Though actually, many teachers and books prefer ethnocentrism for the same idea. Ethnocentricity leans a little more toward “this quality or tendency,” while ethnocentrism names the belief or system — but in real use the two often cover the same ground, and ethnocentrism is the one students will meet more. If a sentence already has the adjective ethnocentric, this is one of the nouns you can reach for.

民族中心性（較學術；日常與 ethnocentrism 常指同一件事）