Sectarism refers to the excessive attachment and narrow-minded adherence to a particular sect or faction, usually related to religion or politics. Synonyms for this term include religious fanaticism, bigotry, dogmatism, sectarian bias, sectarianism, denominationalism, tunnel vision, narrow-mindedness, insularity, and tribalism. These words all refer to an inability or unwillingness to see beyond one's own perspective and beliefs, leading to a lack of empathy and understanding for those who hold different views. Sectarism can lead to conflict and division, as well as stifle progress and innovation. It is important to recognize and challenge sectarism in ourselves and in others in order to build a more inclusive and accepting society.