IPA: /ɪnˈvoʊkətɔri/
KK: /ɪnˈvoʊkəˌtɔri/
Relating to or having the quality of calling upon a higher power or spirit, often in a religious or spiritual context.
The priest delivered an invocatory prayer to bless the gathering.
Invocatory is formed from "in-" (meaning into) and "vocare" (meaning to call). The word describes something that is intended to call upon or invoke, often in a spiritual or formal context.
Think of 'calling into' ('in-' means into and 'vocare' means to call') — that's why invocatory refers to something that calls upon a higher power or spirit.