na-adjective, noun
ill-bred; impolite; rude; blunt
Describes a person or behavior that is lacking in proper upbringing or manners, often implying a direct, tactless, or insolent manner. Can be used as a noun or adjectival noun.
彼のぶしつけな質問に、みんな驚いた。
Everyone was surprised by his rude question.
ぶしつけなお願いで恐縮ですが、少
I apologize for the blunt request, but could you spare me a moment?
Rarely used kanji form.
失礼 is a more general term for rudeness or impoliteness, often used in formal apologies. 不躾 specifically implies a lack of proper upbringing or tact, and can sound more personal or judgmental.
無礼 is a stronger, more direct word for insolence or disrespect, often used for intentional rudeness. 不躾 can also imply a lack of social grace rather than deliberate offense.
The word is composed of 不 (negative prefix) and 躾 (discipline, upbringing). The kanji 躾 is a kokuji (Japanese-made character) combining 身 (body) and 美 (beauty), suggesting the cultivation of proper behavior. The exact historical derivation is uncertain, but the term literally means 'not properly brought up'.