IPA: /ˌɛsəˈtɛrɪsɪzəm/
KK: /ˌɛsəˈtɛrɪsɪzəm/
The study or practice of specialized knowledge that is intended for a small group of people, often related to spiritual or mystical beliefs.
Many ancient cultures had their own forms of esotericism that were passed down through secret teachings.
Esotericism is formed from "esoterikos" (meaning inner or within) and the suffix "-ism" (indicating a practice or belief). The term refers to knowledge that is intended for or likely to be understood by only a small number of people, often relating to mystical or obscure teachings.
Think of 'inner' ('esoterikos') knowledge that is meant for a select few, which helps you remember that esotericism refers to specialized or hidden teachings.