loss of the sense of smell
癕 centers on the loss of the sense of smell, a specific medical condition. The given meaning is narrow and does not suggest a broader conceptual cluster.
癕 combines 疒 (sickness) with 雍, which likely contributes the sound ヨウ. The exact historical development of the meaning 'loss of smell' from these components is uncertain.
The sickness enclosure 疒 wraps around 雍. Imagine a sickness that blocks the inner passages, causing a loss of smell.
For ヨウ, imagine a doctor saying 'Yo! You can't smell?' to a patient with this condition: Yo -> ヨウ, and the sickness enclosure confirms the medical context.