This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 疅 is uncertain. It visually contains 田 (field) and 畺, but the original semantic and phonetic roles are unclear.
Since the meaning is unclear, focus on the shape: 田 (field) on the left and 畺 on the right. Imagine an ancient, forgotten boundary marker in a field.
For キョウ, imagine a field (田) with a strange boundary marker that makes a loud 'kyo' sound when you tap it: kyo -> キョウ.