to be healed, to reform
瘳 centers on recovery from illness or moral failing: being healed physically or reforming one's character.
瘳 combines 疒 (sickness) with 翏, which likely contributes the sound and may relate to the idea of recovery or change. The exact historical development is uncertain.
The sickness enclosure 疒 surrounds 翏, a shape that resembles feathers or wings. Picture sickness being lifted away on wings, leaving the person healed and reformed.
For チュウ, imagine a healed person chewing on a celebratory meal: chew -> チュウ, and the sickness is gone.