This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
撽 combines 扌 (hand) with 敫, which likely contributes sound. The exact historical development is uncertain.
The hand radical 扌 beside 敫 suggests an action, but the specific meaning is unclear. Imagine a hand performing an unknown task.
For コウ, picture a hand (扌) making a hollow knocking sound: 'ko' as in 'knock' without the 'n', repeated: ko-ko -> コウ.