sorrowful, mournful, sorrow, grieve
慼 centers on deep emotional pain: feeling sorrowful, mournful, or grieving. It expresses a heavy, heartfelt sadness.
慼 combines 戚 (which historically relates to relatives or grief) with 心 (heart), reinforcing the idea of heartfelt sorrow. The exact historical development of 戚 is complex, but the combination with 心 clearly points to emotional pain.
The top part 戚 suggests grief or mourning, and the bottom 心 is the heart. Together they show a heart weighed down by sorrow.
For セキ, imagine a person so sorrowful they can only manage a weak, sad 'seki' cough, their grief making them physically ill.