How to say "dementia" in Japanese

• 痴呆ちほうCommon
  nounCovers dementia itself, but the word is sensitive and can cause real offense to patients and their families; for that reason 認知症 is the safe choice in nearly every context.
• 認知症にんちしょうCommon
  nounThe term used in medicine, caregiving, and official settings for dementia as a diagnosed condition; the safe choice when discussing the condition with or about other people.
• ぼけCommon
  nounColloquial word whose core senses are dotage and senility; it can stand for dementia in casual talk but easily sounds insulting when said of a person, so prefer 認知症 for the condition.

Use 認知症 for dementia as a medical condition; 痴呆 has the same meaning but is sensitive and best avoided; 「ぼけ」 is the colloquial word for senility or dotage and can sound insulting.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 痴呆ちほうdementia
• 認知症にんちしょうdementia
• ぼけdotage