Word: 痴呆 (chīdāi) 痴呆 dictionary entry chīdāi stupid; dementia Full dictionary entry for 痴呆 Example sentences using 痴呆 2 sentences, showing page 1 of 1. 医生怀疑爷爷患了痴呆。 Yīshēng huáiyí yéye huàn le chīdāi. The doctor suspects my grandfather has developed dementia. 外婆得了痴呆，常常忘事。 Wàipó de le chīdāi, chángcháng wàng shì. My grandmother has dementia and often forgets things.