痴呆
chī dāi · HSK 7
dementia
🧠 chī dāi sounds like CHEE-DYE — the mind is dying away
痴 (chī) means foolish or obsessed, 呆 (dāi) means dull or blank. Together they describe a state where sharpness has faded — the mind gone dull and blank, as in dementia.
呆 — mouth 口 + tree/wood 木
Originally a variant of 保 (to protect), depicting a person carrying a child. Over time the form simplified to 口 over 木 and the meaning shifted to 'dull, foolish, stunned.' Today 呆 mainly means dumbstruck or slow-witted, as in 发呆 (to space out).