esoteric
es.o.ter.ic \.es-*-'ter-ik\ \-i-k(*-)le-\ aj [LL esotericus, fr. Gk eso-terikos, fr. eso-tero-, c]ompar. of eiso-, eso- within, fr. eis into, fr. en in - more at IN 1a: designed for or understood by the specially initiated alone 1b: of or relating to knowledge that is restricted to a small group 2a: limited to a small circle {~ pursuits} 2b: PRIVATE, CONFIDENTIAL {an ~ purpose} - es.o.ter.i.cal.ly av