This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 侙 is uncertain. It combines 亻 (person) with 式, but the original semantic and phonetic roles are unclear.
A person 亻 beside a form or ceremony 式 might suggest someone involved in a ritual, but the meaning is not established.
For チョク, imagine a person 亻 at a ceremony 式 giving a direct, straight chok sound: chok -> チョク.