觫

bound morpheme

used in the word 觳觫 (húsù), describing trembling with fear (especially of animals facing slaughter)

This character does not appear independently in modern Chinese. It is bound to the disyllabic word 觳觫, famously appearing in Mencius (《孟子·梁惠王上》) where King Xuan of Qi describes an ox trembling (觳觫) as it is led to sacrifice. The term conveys a vivid image of physical shaking caused by extreme fear.